Maharashtra State Board Class 6 Science Solutions Chapter 5 Substances in the Surroundings – Their States and Properties

Class 6 Science Chapter 5 Substances in the Surroundings – Their States and Properties Textbook Questions and Answers

1. In the paragraph below write ‘solid’, ‘liquid’ or ‘gas’ in each of the blank (brackets) depending on the substance referred to just before.

Question a.
On a bright sunny day, Riya and Gargi are playing with a ball (…..) in the park. Gargi feels thirsty. So, Riya brings tender coconut water (…..) for her. At the same time, a strong breeze (…..) starts blowing and it also begins to rain (…..). They run back into the house (…..), change their clothes (…..) and then their mother gives them a cup (…..) of hot milk (…..) to drink.
Answer:
solid, liquid, gas, liquid, solid, solid, solid, liquid.

2. Discuss.

Question a.
Riya pours some water from her bottle into another bottle. Does it change the shape of the water?
Answer:
Yes, the shape of water changes as water is in liquid state. Liquids do not have a shape of its own. They take the shape of the container.

Question b.
Halima picks up a small stone from the ground and puts it in the water in a dish. Does the shape of the stone change?
Answer:
No, the shape of the stone does not change. Stone is a solid, hence retains its shape.

3. Write the properties of these substances.
(water, glass, chalk, iron ball, sugar, salt, flour, coal, soil, pen, ink, soap)

Question a.
Write the properties of these substances.
(water, glass, chalk, iron ball, sugar, salt, flour, coal, soil, pen, ink, soap)
Answer:
Properties of substances:

4. What is sublimation? Write the names of everyday substances that sublimate.

Question a.
What is sublimation? Write the names of everyday substances that sublimate.
Answer:

1. The change of a solid substance directly into a gas or vapour without first changing into liquid is called sublimation.
2. Substances that sublimate: Camphor, napthalene balls, ammonium chloride, iodine.

5. What is made from? Why? 
a. A sickle to cut sugarcane.
b. The sheets used for roofing.
c. A screwdriver
d. A pair of tongs.
e. Electric cables.
f. Ornaments.
g. Pots and pans.

Question a.
A sickle to cut sugarcane.
Answer:
A sickle is made of iron. An iron sickle is hard and malleable. When sharpened it will be able to cut the hard sugarcane.

Question b.
The sheets used for roofing:
Answer:

1. The sheets used for roofing are made of plastic, aluminium.
2. Plastic is hard, hence, protects against weather conditions.
3. Plastic is transparent, hence, sunlight can pass through it.
4. Aluminium is hard, light weight and durable, hence, protects against all weather conditions.
5. Malleable hence formed into thin sheets.

Question c.
A screwdriver:
Answer:

1. A screwdriver is made up of iron, steel, aluminium.
2. A screwdriver possesses property of hardness hence, it easily pierces a screw in piece of wood, wall, metals etc.

Question d.
A pair of tongs:
Answer:

1. A pair of tongs are made up of iron, steel aluminium etc. Tongs are used to lift hot, boiling utensils or vessels.
2. Tongs are hard, ductile and malleable.
3. Hence, have strong grip to hold utensils.
4. Rubbers fitted on the ends will protect from thermal conduction, from bums.

Question e.
Electric cables:
Answer:

1. Electric cables are metal wires (thin) wound in plastic.
2. Metal wires possess the property of hardness, ductility, electrical conductivity.
3. Plastic /rubber covering possesses the property of hardness, elasticity and are bad conductors of heat and electricity.

Question f.
Ornaments:
Answer:

1. They are made up of metals like gold and silver.
2. They possess the property of hardness, ductility, malleability, lustre.

Question g.
Pots and pans: Answer:

1. They are used to cook food, hence metals like aluminium, steel are used.
2. They possess the property of hardness, ductility, malleability, thermal conductivity, electrical conductivity, (microwave ovens)

6. What will happen if ….? And why?

Question a.
Nails are made of plastic
Answer:
If nails are made of plastic, they will not be able to pierce through other substances on being pushed or forced by a hammer. Plastic lacks the property of hardness.

Question b.
A bell is made of wood.
Answer:

1. If a bell is made of wood it will never make a ringing sound. A wooden bell does not have the property of being sonorous.
2. Sonority is the property of metals to produce a ringing sound.

Question c.
Rubber is not fitted on a pair of tongs.
Answer:

1. Rubber is a bad conductor of heat and electricity. It will not allow heat to pass to the hands/handle of the tongs, thus protecting us.
2. Pair of tongs are made up of metals which conduct heat and electricity. They have file property of thermal conduction and electrical conduction.
3. If rubber is not fitted on a pair of tongs, we will not be able to lift hot objects with it.

Question d.
A knife is made of wood.
Answer:
Wood does not have the property of malleability. Therefore, the edge of wooden knife will be blunt. Hence, we will not be able to cut anything with it.

Question e.
An axe is made of rubber.
Answer:

1. If an axe is made of rubber, it will not be used to cut wood or tree.
2. Rubber does not have the property of hardness that is required to push through to cut it.

7. Who am I?

Question a.
I’m found in a thermometer, I measure your temperature.
Answer:
Mercury

Question b.
I make things hot or cold.
Answer:
Heat

Question c.
I have no shape whatsoever!
Answer:
Liquid, gases

Question d.
I dissolve in water, but not in kerosene.
Answer:
Salt

8. Why does this happen? 

Question a.
Coconut oil thickens in winter.
Answer:
Coconut oil is in liquid state. In winter the surrounding temperature / atmospheric temperature starts decreasing. Coconut oil starts cooling or losing heat, it changes to solid state.
Thus coconut oil thickens in winter.

Question b.
Kerosene left open in a dish disappears.
Answer:
When kerosene is left open in a dish, it is exposed to surrounding temperature. As the temperature is more, kerosene starts continuously evaporating and finally disappears.

Question c.
The fragrance of incense sticks lighted in one corner of a room spreads to the other corner.
Answer:
The fragrance of incense sticks is given out in the form of scented vapours. As vapours are in gaseous state, the gas molecules spread out in the room. The molecules of gas move very fast and there are no forces to stop them from going apart. Therefore the fragrance of incense sticks lighted in one corner of room spreads to the other corner.

Question d.
What you see in the picture.

Answer:
The mass of plastic ball is less than an apple. This difference is because of their densities. Since an apple has greater density, it will sink to the bottom on other hand the plastic ball has lesser density, it will float over water surface.

Activity: 

Question 1.
Find out how the big statues of wax are made.

Question 2.
Visit a jeweller’s shop and find out how ornaments are made.

Class 6 Science Chapter 5 Substances in the Surroundings – Their States and Properties Important Questions and Answers

Fill in the blanks:

Question 1.
The state of a substance changes if it is …………… or …………… .
Answer:
heated, cooled

Question 2.
Every substance in our surroundings is found in either the ……………, …………… or gaseous state.
Answer:
solid, liquid

Question 3.
On …………… heat, the substance changes from solid to liquid and liquid to gas.
Answer:
gaining

Question 4.
When the substance cools, or …………… heat, it changes from gaseous to liquid and liquid to solid state.
Answer:
loses

Question 5.
A …………… amount of heat must be gained or lost before the state of a substance can change.
Answer:
specific

Question 6.
When a substance gets heat, it becomes …………… and then …………… .
Answer:
warm, hot

Question 7.
If the substance is very hot, we could get …………… .
Answer:
scalded

Question 8.
A thermometer is used to measure …………… .
Answer:
temperature

Question 9.
…………… is the unit of measuring temperature.
Answer:
Degree Celsius (°C)

Question 10.
Nowadays, …………… thermometers are frequently used.
Answer:
digital

Question 11.
Solids have a shape of its …………… .
Answer:
own

Question 12.
Solids have a …………… volume.
Answer:
definite

Question 13.
Liquids take the shape of the …………… .
Answer:
container

Question 14.
Liquids have a …………… volume.
Answer:
specific

Question 15.
Air occupies all the available …………… .
Answer:
space

Question 16.
Evaporation occurs from the …………… of the water.
Answer:
surface

Question 17.
At sea-level, pure water boils at …………… .
Answer:
100°C

Question 18.
Condensation of steam takes place at …………… .
Answer:
100°C

Question 19.
The temperature of a substance can fall below …………… .
Answer:
0°C

Question 20.
Ice melts at …………… .
Answer:
0°C

Question 21.
Each substance has a specific boiling point which is also its …………… point.
Answer:
condensation

Question 22.
Each substance has a specific melting point which is the same as its …………… point.
Answer:
freezing

Question 23.
Candles are made by melting …………… wax.
Answer:
paraffin

Question 24.
Solid carbon-dioxide is …………… .
Answer:
dry ice

Question 25.
Liquid …………… is used in animal husbandry.
Answer:
nitrogen

Question 26.
Sand is melted to make …………… .
Answer:
glass

Question 27.
Iron is melted to make …………… .
Answer:
tools

Question 28.
Substances can be identified by studying their …………… .
Answer:
properties

Question 29.
Substances that break into small particles are said to be …………… .
Answer:
brittle

Question 30.
The …………… of any liquid is determined by how easily it flows.
Answer:
fluidity

Question 31.
Between substances of the same volume, the ones with greater density are …………… than those of lesser density.
Answer:
heavier

Question 32.
The property of a substance of getting …………… is called its solubility.
Answer:
dissolved

Question 33.
Minerals from the earth’s crust are …………… to obtain metals.
Answer:
processed

Question 34.
Metals can be converted into …………… by hammering.
Answer:
sheets

Question 35.
Metals can be stretched and drawn into …………… .
Answer:
wires

Question 36.
All metals are …………… of electricity to a greater or lesser extent.
Answer:
conductors

Question 37.
Every metal has a …………… colour by which it can be identified.
Answer:
specific

Question 38.
Metals produce …………… sound.
Answer:
ringing

Question 39.
Metals form a …………… group of substances.
Answer:
separate

Question 40.
Heat is the cause of the change of the state of …………… .
Answer:
substances

Match the columns:

Question 1.

Answer:

Answer in one sentence:

Question 1.
What is change of state of substances?
Answer:
When a substance changes from one state to another, the process is called change of state of the substance.

Question 2.
When does state of substance change?
Answer:
State of substance changes when it is heated or cooled.

Question 3.
In which state do substances exist in our surroundings?
Answer:
The substances exist in solid, liquid and gaseous form in our surroundings.

Question 4.
What happens when a substance gains heat?
Answer:
When a substance gains heat, it changes its state i.e. from solid to liquid and liquid to gas.

Question 5.
What happens when a substance loses heat?
Answer:
When a substance loses heat, it changes its state from gaseous to liquid and liquid to solid state.

Question 6.
How do we tell how hot or cold a substance is?
Answer:
The temperature on the thermometer will tell us how hot or cold a substance is.

Question 7.
What is the unit of measuring temperature.
Answer:
Degrees Celsius (°C) is the unit of measuring temperature.

Question 8.
What is the boiling point of water?
Answer:
The boiling point of water is 100° C.

Question 9.
What is condensation?
Answer:
When vapour cools, it is converted into liquid again. This process is condensation.

Question 10.
At what temperature condensation of steam takes place?
Answer:
Condensation of steam takes place at 100° C.

Question 11.
What is the freezing point of water?
Answer:
0° C is the freezing point of water.

Question 12.
What is the temperature of air in the freezer of a refrigerator?
Answer:
-18° C is the temperature of air in the freezer of a refrigerator.

Question 13.
At what temperature ice melts?
Answer:
Ice melts at 0° C.

Question 14.
How are candles made?
Answer:
Candles are made by melting paraffin wax.

Question 15.
What is the use of solid carbon-dioxide?
Answer:
Solid carbon-dioxide (dry ice) is used to make ice cream and to keep it frozen.

Question 16.
What is the use of liquid nitrogen?
Answer:
Liquid nitrogen is used in animal husbandry.

Question 17.
What is sublimation?
Answer:
The change of a solid substance directly into gas or vapour without changing into a liquid is called sublimation.

Question 18.
Define brittleness / What is brittleness?
Answer:
Some substances break into small pieces or particles. Such substances are said to be brittle. This property of substances is called brittleness.

Question 19.
Define hardness / What is hardness?
Answer:
The hardness of a substance is determined by how much resistance it offers to the substances being pushed through it.

Question 20.
Define elasticity / What is elasticity?
Answer:
Some substances change their shape when a force is applied on them but return to their original shape and size when the force is removed. This property is called elasticity.

Question 21.
Define fluidity / What is fluidity?
Answer:
Liquids flow downward on a sloping surface. This property is called fluidity.

Question 22.
How is fluidity of any liquid determined?
Answer:
Fluidity of any liquid is determined by how easily it flows.

Question 23.
Define density / What is density?
Answer:
The mass of different substances having the same volume can be different. This difference is because of the difference in their densities. Between substances of the same volume, the ones with greater density are heavier than those of lesser density.

Question 24.
Define solubility / What is solubility?
Answer:
The property of a substance of getting dissolved is called its solubility.

Question 25.
Define transparency / What is transparency?
Answer:
When we can look through a substance and see things on the other side, then that substance is said to be transparent. This property of the substances is called transparency.

Question 26.
List some transparent substances.
Answer:
Glass, air, clean water and some types of plastic are transparent substances.

Question 27.
What are metals?
Answer:
Metals are substances like copper, gold, iron, aluminium. They are found in the form of minerals deep inside the earth. Minerals from the earth’s crust are processed to obtain metals.

Question 28.
Define malleability. / What is malleability?
Answer:
Metals can be converted into sheets by hammering. This property of metals is called malleability.

Question 29.
Define ductility. / What is ductility?
Answer:
Metals can be stretched and drawn into thin wires. This property of metals is called ductility

Question 30.
Name some ductile metals.
Answer:
Metals like silver, gold, platinum can be drawn into fine wires.

Question 31.
Define electrical conductivity. / What is electrical conduction?
Answer:
Electricity flows through metals. All metals are conductors of electricity to a greater or lesser extent.

Question 32.
Define thermal conductivity. / What is thermal conductivity?
Answer:
Metals allow heat to flow through them. This property is called thermal conductivity

Question 33.
What is lustre?
Answer:
The typical shine or characteristic colour by which metal can be identified is called lustre.

Question 34.
What is sonority of metals? / Define sonority.
Answer;
Metals produce a ringing sound. This property is called the sonority of metals.

Give scientific reasons for following:

Question 1.
Metals are used to make musical instruments.
Answer:
Metals possess the property of being sonorous, i.e. produce a ringing sound. Hence, they are used to make musical instruments.

Question 2.
Ornaments are made up of metals.
Answer:
Metals have the property of being malleable, ductile, lustrous. Hence, ornaments are made up of metals.

Question 3.
Why should we not put our hand or finger in the water to judge the hotness of water?
Answer:
We should never put our hand or finger in the water to judge how hot it is because that is not an accurate measure. Besides if the substance is very hot, we could get scalded.

Can you tell?

Question 1.
Why are electric boards fitted on the wall made of plastic or wood?
Answer:
Plastic or wood are bad conductors of heat and electricity. Electric boards are made up of plastic or wood. So that while touching we will not get electric shock.

Question 2.
The handle of cooker is made of plastic. Why?
Answer:
Cooker is made of metal. When food is cooked in it, it gets heated and the whole of its body becomes hot due to thermal conductivity. Hence with the plastic handle we can easily lift the hot cooker as plastic is a bad conductor of heat.

Question 3.
Use your brain power!
On opening a box of camphor, its smell spreads all around. Why does this happen?
Answer:

1. Camphor is a sublimate substance.
2. When a box of camphor is opened it changes its state from solid to gas or vapour state.
3. This change takes due to the process of sublimation where camphor absorbs heat from surrounding to change from solid to gaseous state.
4. Camphor particles in gaseous state start spreading all around.
5. Hence on opening a box of camphor its smell spreads all around.

Question 4.
Identify the objects shown in fig. 5.14. From which substances are they made? What are these substances called as a group?
Answer:
In fig 5.14, the metallic bars are shown, these bars are made up of shiny solid. These substances are called metals.

Question 5.
Name the solid, liquid and gaseous states of water.
Answer:

• Solid- Ice
• Liquid – water
• Gas – water vapour.

Question 6.
Read this list of substances:
spirit, camphor, petrol, ghee, coconut oil, naphthalene balls, ammonium chloride (navsagar).

Question a.
Which one freezes in winter?
Answer:
Coconut oil, ghee.

Question b.
Which liquids have you seen change into a vapour?
Answer:
Spirit, petrol.

Question c.
Which solid directly changes into gaseous state?
Answer:
Camphor, naphthalene balls, ammonium chloride.

Question 7.
The chart given below shows the boiling point and freezing point of some substances. State whether these substances are solid, liquid or gaseous at room temperature.

Answer:
Candle, plastic and iron are in solid state at room temperature.

Distinguish between solids, liquids and gases.
Answer:

Distinguish between Boiling and Melting.
Answer:

Answer the following briefly:

Question 1.
List properties of solids
Answer:

1. Solids have its own shape i.e. Retains shape, no matter how it is kept.
2. Solids have definite volume.
3. e.g. Sand when poured on a flat surface form a heap.

Question 2.
List properties of liquids.
Answer:

1. Liquid does not have a shape of its own. Takes the shape of the container.
2. A liquid has a specific volume i.e. occupies definite portion of a container.
3. Liquids: e.g. water, milk, kerosene.

Question 3.
List properties of gases.
Answer:

1. Gases does not have a shape of its own.
2. Occupies all the available space.
3. Does not have a definite volume.
4. e.g. Air.

Question 4.
Explain with example how liquids take the shape of the surface.
Answer:
Liquids have a specific volume. They occupy definite portion of a container. Liquids spreads on a flat surface on pouring. Liquids flow downwards along a slope.

Question 5.
Explain Ebullition.
Answer:

1. As the water gets heated, its temperature increases and it evaporates at a faster and faster rate.
2. When water kept on a stove attains a particular temperature or level of heat, then evaporation takes place in all parts of the body of water.
3. Then we see water bubbles rising at a faster and faster rate to the surface and steam mixing in the air.
4. This is called boiling of water or Ebullition.

Question 6.
Explain: Boiling point and condensation point of water are one and the same.
Answer:
Water boils at 100°C. i.e. boiling point of water is 100°C. Condensation of steam also takes place at 100° C. Thus boiling point and condensation point of water are one and the same.

Question 7.
Explain freezing point of water.
Answer:

1. Water kept in a fridge or on ice becomes cooler and cooler i.e. its temperature falls.
2. At a certain temperature water does not cool further but starts freezing and forms ice.
3. The temperature at which this happens is called the freezing point of water. (0° C)

Question 8.
Explain: Freezing point and melting point of water are same.
Answer:

1. The temperature at which water does not get any cooler but starts freezing and forming ice is 0° C.
2. When ice gets heat, it starts melting or changes into liquid state at 0° C.
3. Thus, freezing point and melting point of water are one and the same.

Question 9.
List various uses of changes in physical state.
Answer:

1. Candles are made by melting paraffin wax.
2. Solid carbon-dioxide (dry ice) is used to make ice-cream and to keep it frozen.
3. Liquid nitrogen is used in animal husbandry.
4. Sand (silica) is melted to make glass.
5. Metals like gold and silver are melted to make ornaments.
6. Iron is melted to make tools.

Question 10.
List the properties of substances:
Answer:
The properties of substances are

1. Brittleness
2. Hardness
3. Elasticity
4. Fluidity
5. Density
6. Solubility
7. Transparency

Question 11.
List properties of metals:
Answer:
The properties of metals are

1. Malleability
2. Ductility
3. Electrical conductivity
4. Thermal conductivity
5. Lustre
6. Sonority

Question 12.
How can we change the volume of a gas?
Answer:
On changing the pressure on a gas in a closed container we can change its volume.

Can you tell?

Question 1.
Does water change into vapour the moment we place the vessel on a stove? Does water kept in fridge change at once into ice?
Answer:
No, it doesn’t. Water slowly changes from one state to another.

Question 2.
How do we tell how hot or cold a substance is?
Answer:
A thermometer is used to measure the temperature of the subatance which tell us hot or cold it is.

Question 3.
How will you identify the following

Question i.
A glass: Is it made of plastic, steel or glass?
Answer:
Glass is made of glass as it is transparent.

Question ii.
A rod: Iron or aluminium.
Answer:
A rod is made of iron as it is heavy.

Question iii.
A door: Wooden or glass?
Answer:
A door is wooden as it is opaque.

Question iv.
A white powder: Salt or chalk powder?
Answer:
If powder dissloves in water it is salt and if it does not dissolves in water it is chalk.

Maharashtra State Board Class 6 Science Solutions Chapter 12 Simple Machines

Class 6 Science Chapter 12 Simple Machines Textbook Questions and Answers

1. Classify the following as a lever, a pulley and an inclined plane:
(A wedge, a needle, a staircase, a slide, the wheel of a flagpole, nutcrackers, scissors, an opener, an axe, a crane, a knife)

Question a.
Classify the following as a lever, a pulley and an inclined plane:
(A wedge, a needle, a staircase, a slide, the wheel of a flagpole, nutcrackers, scissors, an opener, an axe, a crane, a knife)
Answer:

2. Fill in the blanks using the proper word and complete the statements.

Question a.
The ………….. in the centre, the ………….. on one side and the on the ………….. other side make a lever of the first order.
Answer:
Fulcrum, load and effort

Question b.
The ………….. in the centre, the ………….. on one side and the ………….. on the other side make a lever of the second order.
Answer:
Load, fulcrum, effort

Question c.
The ………….. in the centre, the ………….. on one side and the ………….. on the other side make a lever of the third order.
Answer:
Effort, fulcrum, load

3. Which machines will you use to do the following work? Write their types.

Question a.
To remove the lid of a tin. Opener Lever of the second order
Answer:

• Work: To remove the lid of a tin.
• Machine: Opener
• Machine: Lever of the second order

Question b.
To lift bricks to the top of a tall building Crane Complex machine
Answer:

• Work: To lift bricks to the top of a tall building
• Machine: Crane
• Machine: Complex machine

Question c.
To cut vegetable Knife Wedge – Simple machine
Answer:

• Work: To cut vegetable
• Machine: Knife
• Machine: Wedge – Simple machine

Question d.
To draw water from a well Pulley Simple machine
Answer:

• Work: To draw water from a well
• Machine: Pulley
• Machine: Simple machine

Question e.
To hold a papad for roasting it. A pair of tongs Lever of the third order
Answer:

• Work: To hold a papad for roasting it.
• Machine: A pair of tongs
• Machine: Lever of the third order

4. Write the answers to the following questions in your own words. 

Question a.
What is meant by a simple machine?
Answer:

1. Machines which have only one or two parts and a simple and easy structure are simple machines.
2. Example: the bottle opener, nail cutter.
3. Simple machines can be handled easily.
4. We use many simple machines in our day to day life.

Question b.
Mention the advantages of using a machine.
Answer:

1. Machines, simple or complex, are used to get more work done in less time and with less effort.
2. Machines are used to accomplish certain tasks more easily.
3. Use of simple or complex machines depends upon the task to be carried out and the time and the efforts required to do it.

Question c.
What is meant by a complex machine?
Answer:

1. Complex machines have many parts which carry out many processes for completing a task.
2. For this purpose the parts are joined to one another.
3. Therefore, these machines are called complex machines.
4. Some of the parts of such complex machines are actually simple machines.
5. The structure of complex machine is complicated.

Question d.
What is a lever? How is the order of the lever determined?
Answer:

1. Lever is a simple machine made up of 3 parts: Load, effort and fulcrum.
2. Order of the lever are determined on the position of the effort, the fulcrum and the load.

5. Why is this so?

Question a.
Traveller’s bags have wheels.
Answer:

1. Combination of wheel and axle is a simple machine.
2. When the axle starts rotating due to force applied, the wheel fitted to it also starts rotating.
3. This makes easier for travellers to carry heavy load.
4. Instead of lifting heavy bag, to drawing it on wheels require less energy. Therefore, traveller’s bag have wheels.

Question b.
Machines have to be maintained.
Answer:

1. Parts of machines rub against one another when they are used.
2. Soiled, dusty parts create more friction. Some parts are affected by the weather, rust and corrosion.
3. Machines get damaged or become useless due to such wear and tear. Hence to avoid this, machines should be maintained properly to keep them in good working condition.

Question c.
A bicycle is said to be a complex machine.
Answer:

1. Bicycle has a complicated structure.
2. Bicycle has many parts which carry out many processes for completing a task.
3. Many parts of bicycle such as pedals, wheels, axle, handle are actually simple machines.
4. The parts of a bicycle are joined to one another – making it a complex machine.

6. Name the levers mentioned in the following passage. Identify the fulcrum, load and effort of each and say which type of lever it is.

Ravi and Savita sit on a sea-saw in a garden. In the mean time, a gardener is trimming trees in the garden. He puts the leaves and other garbage in the wheelbarrow. Later, Ravi gets thirsty and he buys lemon sherbet. The sherbet seller cuts the lemon and squeezes it using a lemon squeezer. He puts small pieces of ice in the glass with the help of the tongs.

Question a.
Name the levers mentioned in the following passage. Identify the fulcrum, load and effort of each and say which type of lever it is.

Ravi and Savita sit on a sea-saw in a garden. In the mean time, a gardener is trimming trees in the garden. He puts the leaves and other garbage in the wheelbarrow. Later, Ravi gets thirsty and he buys lemon sherbet. The sherbet seller cuts the lemon and squeezes it using a lemon squeezer. He puts small pieces of ice in the glass with the help of the tongs.
Answer:
Levers:

1. See – saw – lever of the first order.
   Load – fulcrum – effort.
2. Wheelbarrow – lever of the second order.
   Fulcrum – load – effort.
3. Lemon squeezers – lever of the second order.
   Fulcrum – load – effort.
4. Tongs – lever of the third order.
   Fulcrum – effort – load.

Activity:

Question 1.
Make a list of the various machines used in your home and neighborhood and write their types.

Question 2.
Go to a bicycle repair shop, observe how a bicycle is repaired, and note down the information.

Class 6 Science Chapter 12 Simple Machines Important Questions and Answers

Fill in the blanks.

Question 1.
Simple machines can be handled ………….. .
Answer:
easily

Question 2.
The structure of complex machine is ………….. .
Answer:
complicated

Question 3.
The more gradual the the ………….. lesser is the we bear. But, such an inclined plane is ………….. .
Answer:
slope, weight, longer

Question 4.
The steeper the ………….. , the ………….. is the inclined plane. But we have to bear a …………. weight.
Answer:
slope, shorter, greater

Question 5.
A screw is like a rolled up inclined plane made of an ………….. strip.
Answer:
iron

Question 6.
A wedge is used for ………… an object into two pieces or to ………….. the objects stuck together.
Answer:
breaking, separate

Question 7.
A farmer uses a strong …………. to remove the big stone bogged down in the farm.
Answer:
crow-bar

Question 8.
A device with a grooved wheel and thread designed to lift weights is called a …………. .
Answer:
pulley

Question 9.
When we use a pulley, force is applied in the downward direction for lifting the weight in an …………. direction.
Answer:
upward

Question 10.
Combination of an axle and a wheel is a …………. machine.
Answer:
simple

Question 11.
A needle and a nail are also kind of …………. .
Answer:
wedge

Question 12.
Machines are covered when not in use to prevent …………. settling on them.
Answer:
dust

Question 13.
In Archimedes’ screw, the pipe was placed at an angle of …………. with one end inside the …………. and the rod resting on a …………. .
Answer:
45°, water, flat surface.

Match the columns:

Question 1.

Answer:

Question 2.

Answer:

State whether the following statements are ‘true’ or ‘false’.

Question 1.
Lever helps big vehicle to climb up and down the mountain easily.
Answer:
False

Question 2.
Combination of wheel and axle is a simple machine.
Answer:
True

Question 3.
In pulley, force can be applied in upward direction.
Answer:
False

Question 4.
Screw is an example of wedge.
Answer:
False

Question 5.
In Archimedes screw, the rod rests on flat surface.
Answer:
True

Question 6.
A slanting plank is used to lift a weight.
Answer:
True

Question 7.
A winding road or ghat is an example of lever of first order.
Answer:
False

Answer the following questions in one sentence.

Question 1.
What is a machine?
Answer:
Devices which are used to get more work done in less time and less effort are called machines.

Question 2.
What is a simple machine?
Answer:
Machines which have only one or two parts and a simple and easy structure are called simple machines.

Question 3.
What is a complex machine?
Answer:
Some machines have many parts and they carry out many processes for completing a task. For this purpose, the parts are joined to each other. They are called complex machines.

Question 4.
List the properties of simple machines.
Answer:
Properties of simple machine are:

1. They are made up of only one or two parts.
2. They have a simple and easy structure.
3. They can be handled easily.
4. There are less chances of simple machines breaking down or getting damaged.

Question 5.
List properties of complex machines.
Answer:
Properties of complex machine are:

1. These machines have many parts to carry out many processes.
2. The parts are joined to one another.
3. The structure of complex machines is complicated.
4. Some parts of complex machines are actually simple machines.

Question 6.
What is an inclined plane?
Answer:
A slanting plank which is used to lift a weight on which we bear less weight and lifting becomes easier is an inclined plane.

Question 7.
What is a screw?
Answer:
A screw is like a rolled up inclined plane made up of iron strip.

Question 8.
What is a wedge?
Answer:
A wedge is used for breaking an object into two pieces or to separate objects stuck together.

Question 9.
State examples of wedges.
Answer:
An axle, a knife, a chisel, a needle and a nail are different kinds of wedges.

Question 10.
What is a lever?
Answer:
A lever is a machine made up of 3 parts: effort, load and fulcrum.

Question 11.
What is a fulcrum?
Answer:
The support at which the rod of a lever is rested is called fulcrum of a lever. The lever rotates about the fulcrum.

Question 12.
What is a load?
Answer:
The weight lifted by a lever or the force against which the lever acts is called a load.

Question 13.
What is a load arm?
Answer:
The arm of the lever from the fulcrum to the load is called a load arm.

Question 14.
What is an effort?
Answer:
The force applied on the other end of the rod to lift the load is called an effort.

Question 15.
What is an effort arm?
Answer:
The part of the lever from the fulcrum to the effort is called an effort arm.

Question 16.
What is lever of the first order?
Answer:
The fulcrum is in the centre, the load is at one end while effort is at other end.

Question 17.
What is lever of the second order?
Answer:
The load is in the centre, the fulcrum on one side, and the effort on the other side.

Question 18.
What is lever of the third order?
Answer:
The effort is in the centre, the fulcrum on one side, and the load on the other side.

Question 19.
What is a pulley?
Answer:
A pulley is a device with a grooved wheel and thread designed to lift weights.

Question 2.
How does a pulley help us?
Answer:
If we use a pulley, force can be applied in the downward direction for lifting the weight in an upward direction. It is convenient and easy.

Give scientific reasons:

Question 1.
We use many simple machines in our day-to-day life.
Answer:
Simple machines can be handled easily and there are less chances of these machines breaking down or getting damaged. Hence, we use many simple machines in our day-to-day life.

Question 2.
Less force is required to fit a screw than to hammer a nail.
Answer:

1. A screw is like a rolled-up inclined plane of an iron strip.
2. When a screw is fitted in wood it goes in as if it is going down an inclined plane.
3. Therefore, less force is required to fit a screw than hammer a nail.

Question 3.
Big vehicles easily climb up and down the mountains than a pathway.
Answer:
A winding road or ghat that goes up a mountain is like an inclined plane wrapped around the mountain. It helps big vehicles to climb, up and down the mountain easily.

Question 4.
Oil or lubricant is released between parts of machine.
Answer:
Oil or lubricant is released between parts that rub against each other so that there is less friction between them and wearing is reduced.

Question 5.
Machines are covered when not in use.
Answer:
Machines are covered when not in use to prevent dust settling on them.

Question 6.
How are machines protected from the effect of weather?
Answer:
To prevent the effect of weather, metallic parts in a machine are painted externally and the machines are always kept dry.

Draw the neat and labelled diagram of following:

Question 1.
The screw as an inclined plane.
Answer:

Question 2.
Archimedes’ screw
Answer:

Observe the following diagram and identify the order of lever.

Question 1.
Removing the lid.
Answer:

Question 2.
Picking up an object.
Answer:

Question 3.
Lifting a paper weight.

Answer:

1. Lever of the second order
2. lever of third order
3. Level of first order.

Answer each of the question in brief:

Question 1.
With the help of the diagram explain lever of the 1st, 2nd, 3rd order.
Answer:
1. Lever of the First order: The fulcrum is in the centre, the load is at one end, while the effort is at the other end. e.g. scissors

2. Lever of the Second order: The load is in the centre, the fulcrum on one side, and the effort on the other side. e.g. lid opener

3. Lever of the Third order: The effort is in the centre, the fulcrum on one side, and the load on the other side. e.g. Tongs

Question 2.
How can machines be maintained?
Answer:

1. To maintain machines, all its parts are wiped clean.
2. Oil or lubricant is released between parts that rub against each other.
3. Machines are covered, painted externally and always kept dry.

Question 3.
What is an inclined plane? Explain longer and shorter inclined plane.
Answer:

1. A slanting plank used to lift a weight, is called an inclined plane. Because of inclined plane we will experience less weight and weight lifting become easier.
2. Longer inclined plane: When the inclined plane is longer, the slope is more gradual and lesser is the weight we bear.
3. Shorter inclined plane: When the inclined plane is shorter, the slope is steeper and greater is the weight we bear.

Question 6.
Explain the working of a giant wheel.
Answer:

1. The giant wheel is fitted to a rod at its centre. This rod is called an axle.
2. When the axle starts rotating with the help of electricity the wheel fitted to it starts rotating.
3. This combination of an axle and a wheel is a simple machine.

Observe and discuss:

Question 1.
Name the devices and discuss how they help.

Answer:

1. Needle and thread – Stitching of clothes
2. Wheelbarrow – To carry materials.
3. Opener – To open the lids of bottles.
4. Pulley – To lift bucket
5. Nail cutter – To cut nails
6. Axe – To cut wood into small pieces

Can you tell?

Question 1.
Observe the machines shown in the following pictures. For what purposes are they used? Can you name some other machines of this kind?

Answer:

1. Mixer grinder – To grind the foodstuffs
2. Scooter – To ride and reach places
3. Bicycle – To ride and reach places
4. Sewing machine – To stitch clothes
5. Wheel chair – Specially designed for handicapped patients to move around.

Question 2.
Compare the pathway and a road, available to climb the mountain, the time and strength and your convenience, required to reach the mountain top.
Answer:
We can reach the mountain top by climbing the pathway early than by the road. The time required is less but the strength required is more. The road is easy to walk and more time consuming.

Question 3.
If the point of a needle or the edge of a knife become blunt, then the needle does not penetrate the cloth and the knife does not cut into the fruit. Why is this so?
Answer:
The tip of the needle or the edge of a knife becomes blunt due to regular use. Both the knife and the needle lose their sharpness.

Use your brain power!

Question 1.
Which task can be done using a lever?
Answer:
Task such as using a nut cracker, cutting paper with scissors, can be done using a lever.

Question 2.
Some machines we use in our day to day life are shown in picture. What is the type in each of these?

Answer:

• Wheelbarrow – Lever of the third order
• Pair of tongs – Lever of the first order
• See – saw – Lever of the first
• order Cutter – Lever of the second lever
• Pair of Scissors – Lever of the first order.

Question 3.
When the pedal of the bicycle is rotating, the wheel starts rotating. How does this happen?
Answer:
Pedals of the bicycle are connected to the wheels through the axle, when the axle starts rotating, the wheels also start rotating.

Question 4.
Examples of pulley.
Answer:

1. A simple pulley is used to hoist a flag, to draw water from a well.
2. The crane which is used to lift heavy loads is an example of application of pulleys and levers working together.

Maharashtra State Board Class 6 Science Solutions Chapter 13 Sound

Class 6 Science Chapter 13 Sound Textbook Questions and Answers

1. Fill in the blanks with the proper words.

Question a.
The propagation of sound does not occur through a ………….. .
Answer:
vacuum

Question b.
Noise pollution is a …………… issue.
Answer:
social/serious

Question c.
The sound which is disagreeable to our ears is called …………… .
Answer:
noise

Question d.
Noise has adverse effects on our …………….. .
Answer:
health

2. What should we do?

Question a.
The silencer of a motorcycle is broken.
Answer:

1. If the silencer of a motorcycle is broken, vehicle should be immediately taken to the garage for repair.
2. If silencer is not maintained properly, it will continue making loud noise on the road while in motion, resulting in increasing noise pollution.

Question b.
A factory in the surrounding is producing continuous loud noise.
Answer:
Factories should be located at a proper distance away from residential areas. Authorities should be contacted who will control the decibel level.

3. Write the answers in your own words.

Question a.
What is meant by vibration?
Answer:
Vibration of an object is necessary for the production of sound. As long as the object vibrates, the sound is heard. When the vibration stops, the sound also stops.

Question b.
Explain with the help of practical examples how sound is propagated through solids.

Answer:

1. Singing
2. Chirping of birds
3. Bursting of crackers
4. Whispering
5. Whistling
6. Flute
7. Honking
8. Dog barking

Question c.
What is meant by noise pollution?
Answer:
Continuous noise which has ill effects is called noise pollution.

Question d.
What measures will you take to control noise pollution?
Answer:
Measures for preventing noise pollution:

1. As far as possible, we should avoid blowing horns.
2. The volume of the TV or radio in the house should be restricted to those watching the programmes.
3. Vehicles should be maintained properly to reduce the unnecessary sounds they produce.
4. Factories, airports, railway stations and bus stands should be located at the proper distance away from residential area.
5. Planting of trees helps reduce noise as trees act as a natural barrier.

4. Complete the table.

Question a.

Answer:

Project:

Question 1.
Prepare a list of the harsh sounds mheard near your house. Write about those sounds which produce noise pollution.

Question 2.
Collect information about places where loud noise is prohibited and discuss why it is so.

Class 6 Science Chapter 13 Sound Important Questions and Answers

Fill in the blanks:

Question 1.
Some sounds are ……………… and are heard easily.
Answer:
loud

Question 2.
Some sounds are very ……………… and cannot be heard unless we listen attentively.
Answer:
soft

Question 3.
As long as the object ……………… the sound is heard.
Answer:
vibrates

Question 4.
When the vibration ……………… the sound also stops.
Answer:
stops

Question 5.
The intensity of sound is measured in a unit called ……………… .
Answer:
decibels(dB)

Question 6.
The voice box is located in our ……………… .
Answer:
throat

Question 7.
Sound travels in the form of ……………… through air, water and ……………. .
Answer:
waves, solids

Question 8.
The sound is propagated more clearly through a ……………… than through air.
Answer:
solid

Question 9.
Transmission of sound occurs at a different ……………… through different mediums.
Answer:
speed

Question 10.
Continuous noise which may have ill effects, is called noise ……………… .
Answer:
pollution

Question 11.
Some of the sounds that we enjoy can be a ……………… for others.
Answer:
nuisance

Question 12.
The vibration of an object is necessary for the ……………… of sound.
Answer:
production

Answer in one sentence.

Question 1.
List characteristics of sound.
Answer:
Sounds are soft, loud, pleasant and unpleasant.

Question 2.
What do you mean by unpleasant sounds?
Answer:
The sounds by which we get annoyed are called unpleasant sounds.

Question 3.
What do you mean by loud and soft sounds?
Answer:
The sounds which are heard easily, are loud sounds and the sounds which cannot be heard unless we listen attentively, are soft sounds.

Question 4.
Which movement is exhibited by diaphragm of a speaker and a tabla?
Answer:
Diaphragm of a speaker and a tabla exhibit rapid oscillatory motion which gives rise to vibrations.

Question 6.
What is source of the sound?
Answer:
The object due to which sound is produced is called the source of the sound.

Question 7.
What is acoustics?
Answer:
The science of sound, resonance, production, propagation and effects of sound is called acoustics.

Question 8.
What produces sound in living beings?
Answer:
The vibration of the vocal chords in our larynx or voice box produces sound.

Question 9.
On what does quality of sound depend?
Answer:
Quality of sound produced in the larynx depends upon the tautness of the vocal chords.

Question 10.
How is sound propagated?
Answer:
The sound is propagated in the form of waves through air, water or through a solid.

Question 11.
Why is sound heard more clearly through solids?
Answer:
Transmission of sound occurs at a different speed through different mediums. Transmission of sound is faster through a solid than through a liquid and gas.

Question 12.
What is noise?
Answer:
A loud sound is harsh to ears. Such sounds produce noise.

Question 13.
List the effects of very loud or continuous noise on the people.
Answer:

1. Very loud or continuous noise can cause hearing impairment.
2. This can even lead to deafness.
3. It also causes restlessness, irritability and mental exhaustion.

Question 14.
What is noise pollution?
Answer:
Continuous noise which has ill effects is called noise pollution.

Question 15.
How can we prevent noise pollution with respect to watching TV?
Answer:
The volume of the TV or radio in the house should be restricted to those watching the programmes.

Explain the terms.

Question 1.
Propagation of sound:
Answer:
Sound is said to be propagated when sound waves spread in all directions from a source of sound.

Question 2.
Medium of propagation of sound:
Answer:
The substance around a source of sound through which sound waves spread is called the medium of propagation of sound.

Question 3.
Which sounds do you hear during the recess in the school?
Answer:
During the recess in the school, we hear.

1. laughing
2. students running
3. talking loudly
4. ringing of the bell
5. stamping on the staircase
6. shouting

Question 4.
When there is silence in the classroom, close your eyes and sit quietly. Which sounds in your surroundings can you hear now?
Answer:

1. Loud: Laughing, running, talking, horn of cars, marriage procession, school band, teacher’s voice in next classroom.
2. Pleasant: P.T. teacher’s whistle, chirping of birds.
3. Unpleasant: Shouting, bell ringing, stamping on staircase, dog barking, horns of vehicles.

Question 5.
When a song is being played on a radio or a music system in the house, place your hand on its speaker. What do you feel? Put off the music. What do you feel now?
Answer:

1. When a hand is placed on the speakers of the music system, we feel vibrations on the hand.
2. When music is put off, we don’t feel any vibrations on the hand.

Question 6.
When a metal dish falls on the floor; it makes a loud noise. What do we do to stop the noise? What is the effect of that action?
Answer:
To stop the noise of metal dish falling on the floor, quickly put hand on the dish. Vibrations of the metal dish are stopped and the noise stops.

Question 7.
What is it that vibrates when the sounds of sitar, bell, water tap, and breaking of a saucer, etc. are produced?
Answer:
Strings of the sitar, tongs of the bell, water drops hitting the floor of the basin, pieces of saucers that hit the ground vibrate to produce the sounds.

Question 8.
Take a pot full of water. Strike it lightly on the rim. What do you see? Why are waves formed on the water in the pot?
Answer:

1. We see ripples on the water.
2. When we strike the rim of the pot, our striking causes vibrations. These vibrations are transferred or moved from the pot to the water. Hence, water waves/ripples are seen on the water in the pot.

Question 9.
On rubbing balloon filled with water and another filled with air, of which balloon do we hear a clear or sound?
Answer:
We hear a clearer sound of the water balloon.

Question 10.
If a bell is rung in a vacuum container, will its sound be heard outside?
Answer:
Its sound will not be heard outside.

Observe and Discuss.

Observe the figure and answer the questions.

Question 1.
Which of these sounds is pleasant?
Answer:
The singing of the girl is a pleasant sound.

Question 2.
Which sound is a nuisance to people?
Answer:

1. Boy shouting/screaming.
2. Boy moving/ walking with a toy rattle.

Observe the figure and answer the following.

Question 1.
Make a list of all sounds implied in the picture.

Answer:

1. Chirping of bird outside the house on the tree.
2. Collision of two vehicles – honking of the vehicles.
3. Baby crying.
4. Father talking on the phone.
5. Brother playing in the house – jumping.
6. Sister playing the drum – hitting the drum.
7. Sound of TV.
8. Dog barking.
9. Mother talking to the neighbour.

Question 2.
How would this atmosphere affect a person who is not feeling well?
Answer:
This atmosphere is not convenient for a patient who is ill. He cannot take rest.

Question 3.
Would you be able to study in these conditions?
Answer:
No, students cannot study in this condition. They cannot concentrate on their study.

Maharashtra State Board Class 6 Science Solutions Chapter 7 Nutrition and Diet

Class 6 Science Chapter 7 Nutrition and Diet Textbook Questions and Answers

1. Fill in the blanks:

Question a.
The process of intake of food and utilizing it for all life processes is called ……………. .
Answer:
nutrition

Question b.
All the substances in our food which are useful for various body processes are called ………… .
Answer:
nutrients

Question c.
Carbohydrates and …………. provide …………… to our body.
Answer:
fats, energy

Question d.
In a balanced diet, all the nutrients are present in the ……………. proportion.
Answer:
right

Question e.
In the food pyramid, cereals are given the maximum space because they fulfill our …………… requirement.
Answer:
energy

Question f.
Intake of more food than necessary causes ………….. .
Answer:
overnutrition

2. Spot the following in the table of vitamins and minerals.

Question a.
The nutrient present in citrous fruits.
Answer:
Vitamin C

Question b.
Vitamins/minerals present in milk.
Answer:
Vitamin A, Vitamin B, Vitamin D, calcium, phosphorus.

Question c.
Causes and symptoms of night blindness, scurvy, rickets, beriberi.
Answer:

Question d.
Foods required to prevent the above diseases.
Answer:

Question e.
Causes of anaemia.
Answer:
Deficiency of Vitamin B₁₂, iron.

Question f.
Essential mineral for healthy bones and teeth.
Answer:
Calcium, phosphorus.

Question g.
Sensory organ affected due to the deficiency of Vitamin A.
Answer:
Eyes, skin.

3. Choose the correct alternative. 

Question a.
Pulses are a very good source of ……………. .
(1) carbohydrates
(2) proteins
(3) fats
(4) minerals
Answer:
(2) proteins

Question b.
…………. provide maximum energy to our body.
(1) Cereals
(2) Leafy Vegetables
(3) Water
(4) Amla
Answer:
(1) Cereals

Question c.
Goitre is caused by the deficiency of ……….. .
(1) iron
(2) calcium
(3) iodine
(4) potassium
Answer:
(3) iodine

Question d.
……….. is a type of junk food.
(1) Orange
(2) Milk
(3) Bhakri
(4) Chocolate
Answer:
(4) Chocolate

4. Use the food pyramid to select food items of your choice for three days.
Conditions:
1. The diet for all three days should be balanced.
2. There should be variety in the items chosen for the three days.
Answer:

Day 1:
Cereal like cornflakes and milk, apple, roti, sabzi and dal.

Day 2:
Bread and butter with milk, rice/ roti and chicken, curd, any one type of fruit, salad.

Day 3:
Poha, green vegetable and dal with rice or roti, raita, one fruit, vegetable sandwich.

Activity:

Question 1.
Obtain information on simple methods of spotting the adulteration in foodstuffs and try them out.

Class 6 Science Chapter 7 Nutrition and Diet Important Questions and Answers

Choose the correct alternative:

Question 1.
Vitamin ……………. and vitamin …………….. dissolve easily in water.
(a) A, B
(b) B, C
(c) B, D
(d) B, E
Answer:
(b) B, C

Question 2.
……………. carries oxygen to all parts of the body.
(a) Calcium
(b) Iron
(c) Iodine
(d) Sodium?
Answer:
(b) Iron

Question 3.
Deficiency of vitamin ……………. causes excessive bleeding after an injury.
(a) A
(b) B
(c) K
(d) D
Answer:
(c) K

Question 4.
In accordance with the food pyramid, the proportion of ……………. should be least in our diet.
(a) cereals
(b) fruits
(c) milk
(d) oil
Answer:
(d) oil

Question 5.
……………. is a rich source of vitamin C.
(a) Carrot
(b) Amla
(c) Meat
(d) Milk
Answer:
(b) Amla

Question 6.
Children of growing age need to get approximately ……………. to ……………. calories from the food they eat.
(a) 1500-2000
(b) 3150-4150
(c) 2000-2500
(d) All of them
Answer:
(c) 2000-2500

Fill in the blanks:

Question 1.
All food that we consume during the day is together called our ………. .
Answer:
diet

Question 2.
………….. convert milk into yogurt.
Answer:
Probiotics.

Match the columns:

Question 1.

Answer:

Question 2.

Answer:

Question 3.

Answer:

Pick out the odd one:

Question 1.
Chocolate, chapatti, banana, milk
Answer:
Chocolate

Question 2.
Rice, chapatti, carrot, dal.
Answer:
Carrot

Question 3.
Scurvy, Rickets, Beriberi, Goitre.
Answer:
Goitre

Question 4.
Vitamin A, Vitamin C, Vitamin D, Vitamin E
Answer:
Vitamin C

Answer the following:

Question 1.
Why do living things need food and water?
Answer:
Living things take food and water and use them for:

1. Obtaining energy
2. Growth of the body
3. Carrying out day to day functions of the body.
4. Fighting against diseases

Question 2.
Name the main nutrients in our food.
Answer:
There are six main nutrients in our food. They are:

1. Carbohydrates
2. Fats
3. Proteins
4. Fibres
5. Vitamins
6. minerals

Question 3.
How do we get energy from the food?
Answer:

1. We get energy in the form of heat from the food we eat.
2. Heat is measured in kilocalories (calories).
3. Hence, the energy in food items is also measured in kilocalories (calories).

Question 4.
Vitamin C rich food should be eaten raw. Why?
Answer:

1. Vitamin C is very sensitive to heat and light.
2. It is destroyed easily during cooking. Hence, Vitamin C rich food should be eaten raw.

Question 5.
What is balanced diet? Give its significance.
Answer:
A diet containing adequate quantities of all nutrients is called as balanced diet. Significance of a balanced diet are:

1. An increased capacity to work.
2. Good physical and mental health.
3. Increased capacity to fight/resist diseases.
4. Helps in proper growth of the body.

Question 6.
What is obesity? How to avoid obesity?
Answer:

• Obesity is the state of being overweight.
• Junk food eaten frequently causes obesity.
• Obesity is not good for health.

To avoid obesity:

1. Have a balanced diet.
2. Eat whole grains, fruits and vegetables with their skins.
3. Increase use of bicycles.
4. Play more outdoor games.
5. Do not eat if you are not hungry.
6. Do not watch T.V while eating.
7. Avoid precooked, packaged food.
8. Exercise regularly.

Write short notes.

Question 1.
Vitamins:
Answer:
1. Vitamins are vital substances required by our body in small quantities. They help to improve the body’s resistance to diseases. Their deficiency can lead to various diseases, e.g.: deficiency of Vitamin A causes night blindness and that of Vitamin D causes rickets. The sources of vitamins are vegetables, fruits, milk, fish, meat etc.
2. There are two kinds of vitamins – water soluble vitamins and water insoluble vitamins.
3. Vitamin B and Vitamin C are water soluble vitamins because they dissolve easily in water. They are thrown out of the body through the water in sweat and urine. Hence, a regular supply of these vitamins is essential. B₁₇B₂, B₃, B₆, B₉, and Bp are the types of vitamin B.
4. Vitamins A, D, E and K are insoluble in water but are fat soluble vitamins. They get stored in the body.

Question 2.
Probiotics:
Answer:

1. The useful microorganisms which convert milk into yoghurt are present in yoghurt and buttermilk are called probiotics.
2. Lakhs of such useful microorganisms are present in our intestine.
3. They are essential for our health.
4. Hence, to maintain them in our body we should include food rich in probiotics in our daily diet.

Question 3.
Junk food:
Answer:

1. Foods which gives us energy but do not supply the necessary nutrients are called junk food.
2. Foods like chocolate, pizzas, burgers, noodles, fried foods like pakodas are junk food.
3. These foods contain refined flour, sugar and oil in large proportion.
4. If we consume these foods frequently, our body experiences shortage of proteins, vitamins and minerals.
5. This may lead to malnutrition and obesity.

Question 4.
Adulteration of food:
Answer:
To earn more profits, cheaper substances of low quality called adulterants, are mixed with the foodstuffs. The mixing adulterants to foodstuffs is called adulteration of food. Adulterants may be poisonous or harmful and such food is impure and unfit for consumption.
Some of the adulterants added to foodstuffs are given below:

Give scientific reasons:

Question 1.
Deficiency of vitamin B and C are common in our body.
Answer:

1. Vitamin B and vitamin C are water soluble vitamins.
2. They are thrown out of the body through the water in sweat and urine.
3. Hence, a regular supply of these vitamins is essential.
4. If we don’t intake food rich in these vitamins, deficiency occurs.

Question 2.
Exposure to sunlight is essential.
Answer:

1. On exposure to sunlight our body synthesizes Vitamin D from substances in milk, fish, eggs and butter.
2. Its deficiency causes softening of bones (Rickets).
3. Vitamin D helps in absorbing calcium and phosphorous for healthy bones and teeth.
4. Hence, exposure to sunlight is essential.

Complete the tables given below:

1.

2.

3.

Using the food items given below, prepare a balanced diet pyramid.
[Chapatti, banana, carrot, butter, Nan, egg, bread, cheese, dal, spinach, milk]
Answer:

Can you recall?

Question 1.
Which are the various groups of foodstuff? Which main constituents of food do we get?
Answer :
The various groups of foodstuffs are:

1. Milk and milk products, meat, fish, eggs.
2. Cereals and pulses
3. Vegetables and fruits.
4. Fatty substances oil, butter and ghee.

There are six main nutrients in our food: carbohydrates, fats, proteins, fibres, vitamins and minerals.

Question 2.
What trouble do we have to face if we do not get enough fibre from our daily diet?
Answer:
Fibres help in excretion of food, if we do not get enough fibre we will face indigestion and stomach-ache.

Question 3.
What care must be taken to make sure that fibre is not lost or removed from the food we get?
Answer:
We must not over-cook the foodstuff containing fibres. Fruits should be eaten raw.

Maharashtra State Board Class 6 Science Solutions Chapter 14 Light and the Formation of Shadows

Class 6 Science Chapter 14 Light and the Formation of Shadows Textbook Questions and Answers

1. Choose an appropriate word and fill in the blanks.

Question a.
A ……………. is a natural source of light.
Answer:
star

Question b.
A ………….. is an artificial source of light.
Answer:
candle

Question c.
When light passes through a prism, it gets separated into ………….. colours.
Answer:
seven

Question d.
The image obtained in the pinhole camera is …………. .
Answer:
inverted

Question e.
A shadow is formed when an …………… object comes in the way of light.
Answer:
opaque

Question f.
When a ………….. object comes in the way of light, light passes …………… it. options : seven, star, through, transparent, opaque, colors, shape, erect, inverted, luminous, candle.
Answer:
transparent, through

2. Write whether the following objects are luminous or non-luminous.

Question a.

Answer:

3. Match the following.

Question a.

Answer:

4. Write the answers to the following.

Question a.
What things are necessary for the formation of a shadow?
Answer:
Things necessary for the formation of a shadow are:

1. A source of light
2. An object
3. A surface or screen on which the shadow is formed

Question b.
When can an object be seen?
Answer:
We can see an object when reflected rays reach our eyes.

Question c.
What is a shadow?
Answer:

1. If an opaque object comes in the way of a light source, light does not pass through it.
2. As a result the light does not reach a wall or any other surface on the other side of the object.
3. That part remains dark. This dark part is called the shadow of the object.

Project:

Question 1.
Prepare a Newton’s disc.

Question 2.
Find out how to save electricity with the help of the sunlight we receive during the day.

Question 3.
Read a biography of Sir C. V. Raman and find out about the discoveries he made.

Class 6 Science Chapter 14 Light and the Formation of Shadows Important Questions and Answers

Fill in the blanks.

Question 1.
The ……………. is the main natural source of light.
Answer:
Sun

Question 2.
The light emitted by an electric torch is more …………….. than that obtained from a candle.
Answer:
intense

Question 3.
The left and right sides of the original object appear to be …………….. in the mirror.
Answer:
exchanged

Question 4.
The image is as far behind the mirror as the object is in ……………… of it.
Answer:
front

Question 5.
The …………….. of the image is the same as that of the object.
Answer:
height

Question 6.
The materials through which light passes is said to be …………… .
Answer:
transparent

Question 7.
The materials through which light does not pass is said to be ………….. .
Answer:
opaque

Question 8.
The materials through which light passes partially is said to be ………….. .
Answer:
translucent

Question 9.
If an ………….. object comes in the way of a light source, light does not pass it.
Answer:
opaque, through

Question 10.
The shadow of an object formed due to sunlight is ………….. in the mornings and evenings and ……………. in the afternoon.
Answer:
long, short

Question 11.
The shadow of an object is formed only when ………….. does not pass through the object.
Answer:
light

Question 12.
Stars are ………….. .
Answer:
luminous

Question 13.
Planets, satellites are ………….. .
Answer:
non-luminous

Question 14.
The largest sundial is at ………….., New Delhi.
Answer:
Jantar Mantar

Question 15.
………….. is celebrated as National Science Day.
Answer:
28th February

Question 16.
Light travels in a straight line. This is called ………….. .
Answer:
linear propagation of light

Question 17.
The image formed on the diaphragm of the pinhole camera is ………….. .
Answer:
inverted

Question 18.
The kind of shadow an object forms depends upon the ………….. between the ………….., the object and the ………….. or the ………….. on which the shadow is formed.
Answer:
relative distance, source of light, surface, screen

State whether following statements are True or False.

Question 1.
Light travels in a straight line.
Answer:
True

Question 2.
Stars are luminous.
Answer:
True

Question 3.
Image in a pinhole camera is inverted.
Answer:
True

Question 4.
In the afternoon, shadows are long.
Answer:
False

Question 5.
Fireflies are a natural source of light.
Answer:
True

Question 6.
We see the candle clearly when we bend the tube.
Answer:
False

Question 7.
We can see our image clearly in running water.
Answer:
False

Question 8.
Tracing paper is transparent.
Answer:
False

Question 9.
The light obtained from an electric torch is more intense than that obtained from a candle.
Answer:
True

Question 10.
28tn February is celebrated as “National Science day” since 1987 in India.
Answer:
True

Question 11.
Classify the following into natural and man-made/artificial sources of light. (tubelight, light bulb, torch, burning candle, the sun, fireflies, anglerfish, honey mushroom, stars in the night sky, oil lamps, lanterns)
Answer:

Question 12.
Identify the transparent, opaque and translucent objects from among the following. (piece of glass, wax paper, tinted glass, oil paper, white plastic, a tea kettle, a notebook, cloth, water, a wooden cupboard, sheet of notebook.)
Answer:

Question 13.
Classify the following into the type of images they form: Clear image, faint image, no image. (still clear water, cemented wall, wooden surface, new steel dish, flower, glossy granite cladding of a wall, mirror, butter paper).
Answer:

Question 14.
Relate images formed with the surfaces.
Answer:

1. The clear images are formed on plane surfaces.
2. Faint or no images are formed on rough surfaces.

Answer in one sentence.

Question 1.
What are luminous objects?
Answer:
The objects which emit light i.e. which themselves are a source of light, are called luminous objects.

Question 2.
What determines the intensity of light?
Answer:
The intensity of light is determined by the extent to which the objects emit light.

Question 3.
What are non-luminous objects?
Answer:
The objects that are not sources of light themselves are called as non-luminous objects.

Question 4.
What are artificial sources of light?
Answer:
Man-made objects which emit light are artificial sources of light.

Question 5.
What are natural sources of light?
Answer:
Natural substances, materials which emit light are called natural sources of light.

Question 6.
What is linear propagation of light?
Answer:
Property of light travelling in a straight line is linear propagation of light.

Question 7.
What is reflection of light?
Answer:
The rays of light falling on an object from a source of light are thrown back from the substance of that object. This is reflection of light.

Question 8.
How do we see objects around us?
Answer:
The rays of light falling on an object from a source of light are thrown back from the surface of that object. This is called reflection of light. We see the object when the reflected rays reach our eyes.

Question 9.
What is moonlight?
Answer:
Sunlight reflected from the surface of the moon reaching us, in which we see the moon is called the moonlight.

Question 10.
What type of image is formed in the mirror?
Answer:
The image formed in the mirror is ‘laterally inverted’ i.e. right side appears as left side and left side appears as right side.

Question 11.
What change do you see in the image if you decrease or increase your distance from the mirror?
Answer:
When the distance between object and mirror is increased the size of image decreases where as, when the distance is decreased the image size increases.

Question 12.
What difference do you find in the height of the image in the mirror and yourself?
Answer:
The size of the image in the mirror is the same as that of the object.

Question 13.
What is the image on the diaphragm of the pinhole camera?
Answer:
An inverted or an upside down image of the candle is seen on the diaphragm of the pinhole camera.

Question 14.
What do you mean by transparent object?
Answer:
The objects / materials through which light passes are said to be transparent.

Question 15.
What do you mean by opaque materials?
Answer:
The materials through which light does not pass are said to be opaque.

Question 16.
What do you mean by translucent materials?
Answer:
The materials through which light passes partially are said to be translucent.

Question 17.
How is the shadow in the morning, afternoon and evening?
Answer:
The shadows are long in the mornings and evenings and short in the afternoon.

Question 18.
What is shade of a tree?
Answer:
The shade of a tree is its shadow.

Question 19.
How many colours is sunlight made up of?
Answer:
Sunlight is made up of seven colours.

Give reasons for the following.

Question 1.
When we see in the mirror, we see our image in the mirror.
Answer:
When we see our face in the mirror, the light reflected from our face falls on the mirror and gets reflected back again. Hence, we see our image in the mirror.

Question 2.
Opaque materials cast shadow.
Answer:
An opaque material does not allow light to pass. Hence, it casts a shadow.

Question 3.
Transparent and translucent object do not cast a shadow.
Answer:
Translucent objects cast a faint shadow whereas transparent objects do not cast a shadow at all because they allow light to pass through them.

Use your brain power!

Question 1.
Why is the image on the diaphragm of the pinhole camera inverted?
Answer:
1. The pinhole camera works on the principle of light travelling in a straight line.
2. The rays of light from the candle flame go in all directions.
3. We consider only two rays that pass through the hole and fall on the screen.

4. The rays intersect at the pinhole.
5. Since the rays cross over at that point, the top of the object appears at the bottom of the image and the bottom of the image appears at the top. Thus, we see an inverted image of the candle.

Question 2.
How will you light up a dark room using reflected light?
Answer:
Focusing on the wall with torch light. Mirrors or reflectors can be used to get light from outside.

Question 3.
Try to start the TV by operating the remote control from behind it.
Answer:
T.V will not start.

Question 4.
In which step is the flame of the candle seenclearly? Why?

Answer:
In step 1 the flame of the candle is seen clearly because light travels in straight line.

Can you tell?

Question 1.
Can we see anything in total darkness?
Answer:
No, we cannot see anything in total darkness.

Question 2.
What helps us to see the objects around us?
Answer:
Reflected light helps us to see objects around us.

Question 3.
What does the light in each one of the pictures originate form?
Answer:

1. Bulb
2. Firefly
3. Candle
4. Sun

Question 4.
Name the natural sources of light.
Answer:
Sun, Fireflies

Question 5.
In which objects do we see our reflection?
Answer:
All objects reflect light rays, but the best reflectors of light are mirrors, still water in a lake, new steel dish i.e. smooth shiny surfaces.

Question 6.
What difference do you notice on looking through the windows in the picture? What causes the difference? The picture shows transperant, opaque, translucent window panes. Spot them.

Answer:

1. Through the first window we can see a clear picture of things outside.
2. Second window gives a faint image.
3. Through the third window, we can’t see anything
4. The difference in the image is due to the material of the window panes.
5. The first window pane is transparent.
6. The second window pane is translucent.
7. The third window pane is opaque.

Answer the following questions in brief.

Question 1.
List factors on which shadow depends.
Answer:
Shadow depends on relative distance between the source of light, the object and the surface on which the shadow is formed.

Question 2.
How we can see that light travels in straight line.
Answer:

1. In the morning or in the afternoon, rays of light enter a slit in a door, window or a small hole in the roof.
2. As these rays of light from the slit or the hole move towards the floor, the dust particles in their way are clearly seen.
3. Due to these particles, the path of light becomes visible to us.
4. Thus we can see that their path is along straight lines.

Question 3.
What is the difference between an object and its reflection? What causes the difference?
Answer:

1. Object and its reflection result in formation of images.
2. Reflections taking place from highly polished metals, mirrors, still water etc, form clear images.
3. Reflections taking place from wooden surface, flower, book form dull, blurred images.
4. The difference in reflections is caused by the surface of the object.
5. Regular reflections have smooth, polished surfaces, hence, image is clear.
6. Diffused reflections have hard, rough surfaces, hence, image is dull.

Question 4.
List characteristics of images in a plane mirror.
Answer:

1. The left and right sides of the original object appear to be exchanged in the mirror image.
2. The image is as far behind the mirror as the object is in front of it.
3. The size of the image is the same as that of the object.

Question 8.
State the characteristics of image formed by a pinhole camera.
Answer:
Characteristics of an image formed by a pinhole camera are as follows:

1. It is inverted/upside down.
2. It can be obtained on a screen – real image.

Try this.

Question 1.
Make your friend stand in between the torch and the wall. What happens?
Answer:
Friend’s Shadow forms on the wall.

Question 2.
Place a glass filled with water on a sheet of paper in the window so it receives direct sunlight. What is seen on the paper?
Answer:
We see rainbow colours on the paper.

Question 3.
Can we do the same in a dark room with the help of a prism and a torch? What do we learn from this?
Answer:
yes, we can. Light gets seperated into seven colour. From this we learn that white light contains seven colours.

Question 4.
If you dip the wire loop in the soap water and then blow it, soap bubbles are formed. Are the beautiful colours of the rainbow seen in these bubbles?
Answer:
Yes, splitting of white light into different colours takes place.

Question 5.
What do you see on holding a CD in the sun?
Answer:
CD reflects rainbow colours, and interesting : patterns.

Question 6.
Raise your right hand. In mirror which hand of the mirror image is raised?
Answer:
Left hand of the mirror image is raised.

Question 7.
Is there any difference between your height and height of the mirror image?
Answer:
The height remains the same.

Maharashtra State Board Class 6 Science Solutions Chapter 6 Substances in Daily Use

Class 6 Science Chapter 6 Substances in Daily Use Textbook Questions and Answers

1. Fill in the blanks using proper works:

Question a.
Rubber made by vulcanization is a …………… material.
Answer:
hard

Question b.
Man-made materials are made by …………… natural materials.
Answer:
processing

Question c.
…………… thread was developed simultaneously in New York and London.
Answer:
Nylon

Question d.
Rayon is also known as …………… .
Answer:
synthetic silk

2. Answer the following questions. 

Question a.
Why did the need for man-made materials arise?
Answer:
The need for man-made materials arose due to the following reasons:

1. To meet the needs of an increasing population.
2. Human nature to try to make life more comfortable.
3. They can be made available in plenty at a low cost.
4. The reserve of natural substances is decreasing.

c

Question b.
Which are the natural materials obtained from plants and animals?
Answer:
Leather, jute, wool, cotton, silk are the natural substances obtained from plants and animals.

Question c.
What is vulcanization?
Answer:

1. Vulcanization is the process in which rubber is heated with sulphur for three to four hours.
2. Sulphur is mixed to give hardness to rubber.
3. The proportion of sulphur depends on the purpose for which the rubber is to be used.

Question d.
Which natural materials are used to obtain fibres?
Answer:
Cotton, wood pulp and various hydrocarbons obtained from mineral oils are used to obtain fibres.

3. What are we used for?

Question a.
What are we used for?
Answer:

1. Soil: It supports plant life and hence indirectly supports all living things. It is used for making clay pot, utensils, bricks etc.
2. Wood: It is used in paper industry. It is also used to make furniture.
3. Nylon: It is used to manufacture clothes, fishing nets, ropes, etc.
4. Paper. It is used in our textbooks, note books, currency notes, etc.
5. Rubber: It is used in the manufacture of erasers, tyres, rubber toys, rubber bands, etc.

4. How is paper manufactured? Write in your own words.

Question a.
How is paper manufactured? Write in your own words.
Answer:
Coniferous trees like pine trees are used to make paper.

1. The bark of the logs of these trees is first removed and the wood is broken into small pieces.
2. The mixture of these pieces with some chemicals is kept soaked for a long time to form pulp.
3. On completion of chemical process, fibrous substances from wood pulp are separated and some dyes are added.
4. The pulp is then passed through rollers, dried to form paper and finally wound on reels.

5. Give scientific reasons.

Question a.
We must use cotton clothes during summer.
Answer:

1. During summer we sweat more due to high temperature.
2. Cotton clothes absorb sweat.
3. Synthetic clothes are water repellent. They do not absorb sweat and we feel uncomfortable. Hence we must use cotton clothes in summer.

Question b.
We must observe economy in the use of materials.
Answer:

1. Due to excessive use of natural substances by human beings to fulfil their needs; they are getting depleted at a faster rate.
2. At the same time, it takes a very long time for these substances to get naturally formed again.
3. Hence, we must observe economy in the use of materials so that they are available for the future generation also.

Question c.
Saving paper is the need of the hour.
Answer:

1. Saving paper means saving trees as wood is used as the raw material to manufacture paper.
2. Trees are natural habitat for many Living things.
3. Trees help in increasing rainfall and water availability. Hence, saving paper helps in saving trees which in turn maintains balance in nature.

Question d.
Man-made materials have more demand.
Answer:

1. Man-made substances are waterproof, lightweight and easy for transportation.
   Substances in Daily Use
2. They are easier to use and can be made available in plenty at a low cost.
   Hence, there is more demand for man-made materials.

Question e.
Humus is a natural material.
Answer:

1. Humus is obtained from plant and animal wastes.
2. Micro-organisms act on these wastes and convert them into humus.
3. Hence, humus is a natural material.

6. Find out.

Question 1.
How is lac obtained from nature?
Answer:

1. Lac is a resinous substance secreted from the glands present in the skin of female lac insect.
2. Lac insects live on the Palash trees. In India lac is mainly produced in the states of Rajasthan and Bihar.

Question 2.
How are pearls obtained?
Answer:

1. Pearls are formed when a foreign particle such as a grain of sand or a small particle of rock accidentally enters the space between the mantle and shell of an oyster’s body.
2. Oysters cannot reject the particle, and as a defence mechanism its produces a shining coating called nacre on the particle layer by layer.
3. As the shiny layers get added, a pearl is formed.
4. Cultured pearls are artificially formed by inserting a bead in oyster shell and allowed to coat it with nacre over several years.

Activity:

Question 1.
Visit a rubber, paper or textile industry in your area and collect information about it.

Question 2.
Collect various samples of paper and note their uses.

Question 3.
Use blank pages from old note-books and make a new one.

Class 6 Science Chapter 6 Substances in Daily Use Important Questions and Answers

Fill in the blanks using proper works.

Question 1.
Natural rubber is obtained from …………… of trees.
Answer:
latex

Question 2.
Changes where the original constituent substances cannot be obtained again from the new substances are called …………… changes.
Answer:
irreversible

Question 3.
A paper factory in Maharashtra is situated at …………… .
Answer:
Ballarpur

Question 4.
Glass can be made from …………… and …………… .
Answer:
sand, calcium

Question 5.
Botanical name of rubber plant is …………… .
Answer:
Hevea brasiliensis

Question 6.
…………… obtained from mineral oils are used to make polymer chains.
Answer:
Hydrocarbons

Question 7.
The maximum production of rubber in India is in …………… .
Answer:
Kerala

Question 8.
…………… invented the process of vulcanisation.
Answer:
Charles Goodyear

Match the columns:

Question 1.

Answer:

State whether the following statements are ‘true’ or ‘false’.

Question 1.
We can find plastic in nature.
Answer:
False

Question 2.
Soap is a man-made substance.
Answer:
True

Question 3.
We should reuse available resources.
Answer:
True

Question 4.
Nylon clothes are good summer wear.
Answer:
False

Question 5.
Glass is a man-made substance.
Answer:
True

Question 6.
In irreversible changes original substances can be obtained again.
Answer:
False

Question 7.
Rayon is made up of cotton and wood pulp.
Answer:
True

Give two examples of each of the following:

Question 1.
Natural fibres
Answer:
cotton, silk

Question 2.
Synthetic fibres
Answer:
terylene, rayon

Question 3.
Biotic natural substances
Answer:
wool, jute

Question 4.
Abiotic natural substances
Answer:
air, water

Question 5.
Man-made substances.
Answer:
paper, glass

Classify the following substances in the table given below.
(iron, wood, brick, paper, terylene, stone, jute, air, silk, utensils, plastic, rayon, water, wool, dacron, lac, nylon, pearl)
Answer:

Define:

Question 1.
Natural substances.
Answer:
Substances available in nature are called natural substances.

Question 2.
Man-made substances.
Answer:
Man-made substances are new substances produced by processing naturally available resources.

Question 3.
Biotic substances.
Answer:
Natural substances obtained from living things are called biotic substances.

Question 4.
Abiotic substances.
Answer:
Natural substances that are not obtained from living things are called abiotic substances.

Question 5.
Plant-originated substance.
Answer:
A substance obtained from a plant is called a plant-originated substance.

Question 6.
Animal-originated substance.
Answer:
A substances obtained from an animal is called an animal-originated substance.

Question 7.
Hydrocarbons.
Answer:
Substances obtained from mineral oil are called hydrocarbons.

Answer the following in one or two sentences.

Question 1.
Why was Rayon named so?
Answer:
The threads of Rayon have shine and strength. They appeared to be shining bright like the sun’s rays. Hence, they were named ‘Rayon.

Question 2.
How are TV sets, refrigerators, etc. packed? Why?
Answer:
To pack TV sets, refrigerators, etc. big cartons and thermocol are used. These man-made substances are water resistant, light weight and easy for transportation.

Question 3.
Give the properties and uses of nylon.
Answer:
Nylon threads have a shine and are strong, transparent and water resistant. They are used to manufacture clothes, fishing nets, ropes, etc.

Question 4.
What is latex?
Answer:
Latex is a milky white natural substance produced in the stems of rubber trees.

Question 5.
Name the basic material used to obtain paper.
Answer:
Wood is the basic material used in the manufacture of paper.

Question 6.
What kind of paper is used for currency notes manufacturing?
Answer:
Flax fibre is used in the manufacture of currency notes.

Question 7.
Where was the process of making paper invented?
Answer:
The process of making paper was invented in China.

Answer in brief:

Question 1.
What are the advantages of synthetic fibre?
Answer:
Advantages of synthetic fibre are:

1. These fibres can be manufactured on a large scale.
2. They cost less.
3. They are strong and durable.
4. They can be used for a long time.
5. They are water repellent. They dyy easily.
6. They are light weight and comfortable to wear.
7. Clothes made from these threads are wrinkle free and scratch free.

Question 2.
Give the shortcomings of synthetic fibre.
Answer:

1. They are water repellent. Hence, they do not absorb sweat from the skin.
2. Continuous use of these clothes keeps the skin moist which may cause skin diseases.
3. Synthetic clothes are uncomfortable to wear especially in summer.
4. They catch fire easily.
5. If they catch fire, they stick to the skin and cause skin injuries.
6. These fibres are not decomposed by micro-organisms.

Question 3.
Write a short note on natural rubber.
Answer:

1. Rubber is a natural substance obtained by collecting the latex of certain trees.
2. The botanical name of this tree is ‘Hevea brasiliensis’
3. In India, the maximum production of rubber is in Kerala.

Question 4.
What are dacron, terylene and terene?
Answer:

1. Dacron, terelyne and terene are synthetic fibres prepared from hydrocarbons.
2. Various hydrocarbons obtained from mineral oil are used to make polymer chains.
3. A solution of such polymer is pressed through a strainer with fine holes.
4. The fibre formed after cooling are long and unbroken threads.
5. These threads have been named as dacron, terylene and terene.

Give scientific reasons:

Question 1.
Natural substances are depleting.
Answer:

1. Due to increase in population there is an increase in demand. To meet this demand, natural substances are used to a greater extent.
2. Due to human nature to make his life more comfortable, he learnt to use natural resources and also began to process them to make new substances. Hence natural substances are depleting at an alarming rate.

Can you tell?

Question 1.
Difference between leather, jute, wool, cotton and soil, water, metals.
Answer:

1. Leather, jute, wool are biotic natural substances.
2. Soil, water, metals are abiotic natural substances.

Question 2.
How are leather and wool different from jute and cotton?
Answer:
Leather and wool are obtained from animals while jute and cotton are obtained from plants.

Question 3.
Do you find plastic, nylon, brass or cement in nature?
Answer:
No, they are all man-made materials.

Question 4.
Can red chillies become green chillies again?
Answer:
No, the change from green chillies to red chillies is irreversible.

Question 5.
From which substances in nature can we get threads or fibre?
Answer:
Cotton plant, jute, silkworm.

Question 6.
What are clothes made from?
Answer:
Clothes are made from yarn obtained from fibre.

Classify the following substances according to their uses:
sand, soap, wool, window glass, bamboo, cotton, bricks, silk, leafy vegetables, cement, fruits, water, sugar.
Answer:

• For construction: Sand, window glass, bamboo, bricks, cement.
• As food: Leafy vegetables, fruits, water, sugar.
• At home: Soap for cleaning.
• For clothes: Wool, cotton, silk.

Make a list of objects, each of which can be made from several substances.
Answer:

Use your brain power!

Question 1.
Complete the table below, showing how substance of daily use are classified.

Answer:

1. Natural
2. Biotic
3. Cement
4. Animal Origin
5. Cotton

Maharashtra Board Class 6 History Solutions Chapter 5 Religious Trends in Ancient India

Class 6 History Chapter 5 Religious Trends in Ancient India Textbook Questions and Answers

1. Fill in the blanks:

Question 1.
The principle of ______ is very important in Jainism.
(a) justice
(b) casteism
(c) non-violence
Answer:
(c) non-violence

Question 2.
An extraordinary feature of Gautam Buddha’s personality is his ______ for all living beings.
(a) compassion
(b) satisfaction
(c) anger
Answer:
(a) compassion

2. Answer in short:

Question 1.
What were the teachings of Vardhaman Mahavir?
Answer:
Vardhaman Mahavir taught the people that the greatness of man does not depend on his vama, but on his excellent conduct.

Question 2.
Which famous quotes of Gautam Buddha have you read here? What value does it uphold?
Answer:

• One of the famous quotes of Gautam Buddha is that ‘Even the little quail can chirp freely in her nest’, this quote depicts the values of freedom and equality of his preaching.
• Gautam Buddha preached that like men, women too had the right to their own upliftment.

Question 3.
What virtues are emphasized in Judaism?
Answer:
Judaism emphasizes justice, truth, peace, love, compassion, humility, charity, ethical speech and self-respect.

Question 4.
What are the teachings of Christianity?
Answer:

• According to the teachings of Christianity, we are all brothers and sisters.
• We should love everyone even our enemies.
• We should forgive those who err or go wrong.

Question 5.
What are the teachings of Islam?
Answer:

• The teachings of Islam is that Allah is eternal, absolute, all powerful and merciful.
• The purpose of human existence is to worship Allah.
• The Quran Sharif provides guidance as to how man should behave in life.

Question 6.
What is at the core of Parsee thinking?
Answer:
At the core of Parsee thinking are three main principles of conduct, namely, good thoughts, good words and good deeds.

3. Write notes on:

Question 1.
Aryasatya
Answer:
There are four truths at the root of all human affairs. They are called noble truths or Aryasatyas.

• Dukha (suffering): There is suffering in the world.
• The cause of suffering: There is a cause of suffering
• Dukkha – nivaran: It is possible to end suffering.
• Pratipad: Pratipad means the ‘way’ that leads to the end of suffering.

Question 2.
Panchasheel
Answer:
Gautam Buddha asked people to follow five rules called Panchasheel.

• Stay away from killing animals.
• Stay away from stealing.
• Stay away from unethical conduct.
• Stay away from telling lies.
• Stay away from intoxicants.

4. Put the following in the proper place in the chart of the Five Great Vows and the Three Jewels.

• Ahimsa
• Samyak Darshan
• Satya
• Asteya
• Samyak Jnan
• Aparigraha
• Samyak Charitra
• Brahmacharya

Answer:

5. Give reasons:

Question 1.
Why was the name ‘Jina’ given to Vardhaman Mahavir?
Answer:
Vardhaman Mahavir was called Jina or the Conqueror because the joy derived from physical comforts and the discomforts felt due to undesired things had no impact whatsoever on him.

Question 2.
Why did Gautam Buddha came to be called the Buddha?
Answer:
Gautam Buddha has attained knowledge of human life in its entirety. That is why he came to be known as the ‘Buddha’.

Activity:

• Collect the information about and the pictures of various festivals.
• Visit the prayer houses of different religions and describe the precincts in the classroom.

Class 6 History Chapter 5 Religious Trends in Ancient India Additional Important Questions and Answers

Complete the sentence by choosing the correct option:

Question 1.
Towards the end of the Vedic period, the minute details of yajna rites acquired ________ importance.
(a) undue
(b) least
(c) much needed
Answer:
(a) undue

Question 2.
A person’s social position was decided by the ______ into which he was born rather than by his achievements.
(a) ashrama
(b) varna
(c) Kula
Answer:
(b) varna

Question 3.
Jainism is one of the ancient _______ in India.
(a) topic
(b) religions
(c) civilization
Answer:
(b) religions

Question 4.
Vardhaman Mahavir is the _______ Tirthankar in the jain religious tradition.
(a) 24th
(b) 25th
(c) 26th
Answer:
(a) 24th

Question 5.
The principle of is very important in Jainism.
(a) justice
(b) casteism
(c) non-violence
Answer:
(c) non-violence

Question 6.
Vardhaman Mahavir was born in ________, a part of Vaishali.
(a) Kundagram
(b) Gaya
(c) Nepal
Answer:
(a) Kundagram

Question 7.
Vardhaman Mahavir left his house and all comforts for the attainment of ______.
(a) non-violence
(b) knowledge
(c) God
Answer:
(b) knowledge

Question 8.
He attained enlightenment after twelve and a half years of rigorous _______.
(a) tapa
(b) exercise
(c) good health
Answer:
(a) tapa

Question 9.
Vardhaman is said to be _______ because he had the resilience, the courage to conquer all passions.
(a) victorious
(b) saint
(c) Mahavir
Answer:
(c) Mahavir

Question 10.
The _______ held by the Tirthankar to preach to people was known as ‘samavasaran’.
(a) procession
(b) meeting
(c) assembly
Answer:
(c) assembly

Question 11.
Among the teachings of Mahavir, Anekantavada is considered to be very _____ in the quest for truth.
(a) honest
(b) important
(c) nice
Answer:
(b) important

Question 12.
In the Vedic tradition, the doors of knowledge had slowly been closed to ________.
(a) women
(b) men
(c) children
Answer:
(a) women

Question 13.
Gautam Buddha was the founder of ________.
(a) Christianity
(b) Buddhism
(c) Zoroastrianism
Answer:
(b) Buddhism

Question 14.
Gautam Buddha delivered his first sermon at _______ near Varanasi.
(a) Harappa
(b) Sarnath
(c) Lumbini
Answer:
(b) Sarnath

Question 15.
Pratipad means the ‘way’ that leads to the end of ________.
(a) suffering
(b) life
(c) preach
Answer:
(a) suffering

Question 16.
Gautam Buddha created a sangha of bhikkhus to ______ his religion.
(a) stretch
(b) reach
(c) preach
Answer:
(c) preach

Question 17.
People of all varnas and castes could _________ Buddhisms.
(a) reject
(b) embrace
(c) obey
Answer:
(b) embrace

Question 18.
An extraordinary feature of Gautam Buddha’s personality is his _______ for all living beings.
(a) compassion
(b) satisfaction
(c) anger
Answer:
(a) compassion

Question 19.
The tolerance preached by Gautam Buddha is a _____ principle not only for the Indian society but for all mankind even today.
(a) strict
(b) guiding
(c) aggressive
Answer:
(b) guiding

Question 20.
In the ancient period, new religious trends and thoughts went on ______ in India.
(a) emerging
(b) submerging
(c) revolting
Answer:
(a) emerging

Question 21.
Religions like Judaism, Christianity, Islam and Zoroastrianism also took ______ in the Indian society.
(a) stem
(b) branches
(c) root
Answer:
(c) root

Question 22.
A Jewish prayer house is known as ________.
(a) Temple
(b) Church
(c) Synagogue
Answer:
(c) Synagogue

Question 23.
_______ is a religion founded by Jesus Christ.
(a) Hinduism
(b) Christianity
(c) Judaism
Answer:
(b) Christianity

Question 24.
According to the teachings of Christianity there is only ______ God.
(a) three
(b) two
(c) one
Answer:
(c) one

Question 25.
The ________ is the holy book of Christianity.
(a) Geeta
(b) Bible
(c) Avesta
Answer:
(b) Bible

Question 26.
A Christian prayer house is known as ______.
(a) Synagogue
(b) Agyari
(c) Church
Answer:
(c) Church

Question 27.
The Quran Sharif provides guidance as to how a man should ______ in life.
(a) behave
(b) sing
(c) evolve
Answer:
(a) behave

Question 28.
Since ancient times there have been ______ relations between India and Arabia.
(a) friendly
(b) trade
(c) unfriendly
Answer:
(b) trade

Question 29.
The prayer house of ________ is known as a mosque or masjid.
(a) Christians
(b) Muslim
(c) Parsees
Answer:
(b) Muslim

Question 30.
The sacred text of the Parsee or Zoroastrians is the _______.
(a) Bible
(b) Quran
(c) Avesta
Answer:
(c) Avesta

Question 31.
The ______ came to India from the Pars or Fars province of Iran.
(a) Parsees
(b) Muslims
(c) Hindus
Answer:
(a) Parsees

Question 32.
Zarathushtra or Zoroaster was the _______ of the Parsees.
(a) priest
(b) founder
(c) follower
Answer:

Question 33.
_______ is the name of the Zoroastrian God.
(a) Allah
(b) Ahur Mazda
(c) Ram
Answer:
(b) Ahur Mazda

Question 34.
The elements of fire and water are very important in the _______ religion.
(a) Zoroastrian
(b) Judaism
(c) Hinduism
Answer:
(a) Zoroastrian

Question 35.
The sacred fire burns in the temples which is known as _______.
(a) Church
(b) Mosque
(c) Agyaris
Answer:
(c) Agyaris

Match the following:

Question 1.

Answer:
1 – c
2 – a
3 – e
4 – f
5 – b
6 – d

Answer the following in one sentence:

Question 1.
How was a person’s social position decided?
Answer:
In the latter vedic period, a person’s social position was decided by the vama into which he was bom rather than by his achievements.

Question 2.
What led to the establishment of new religions?
Answer:
Many people realized that every person is free to find ways of his own upliftment and this led to the establishment of new religions.

Question 3.
Where was Vardhaman Mahavir born?
Answer:
Vardhaman Mahavir was born in Kundagram, a part of Vaishali in the state of Bihar.

Question 4.
After how long did Vardhaman Mahavir attain enlightenment?
Answer:
Vardhaman Mahavir attained enlightenment after twelve and a half years of rigorous tapa.

Question 5.
What did Jainism lay stress on?
Answer:
Jainism laid great stress on good conduct.

Question 6.
How do we know that equality was practised in Jainism?
Answer:
The assembly held by the Tirthankar to preach to people (samavasaran) was based on equality. People of all varnas had entry to it, hence we know that equality was practised in Jainism.

Question 7.
What is Aparigraha?
Answer:
Man tends to accumulate property due to greed. Aparigraha means not hoarding or accumulating anything in this way.

Question 8.
State the quotes of Vardhaman Mahavir that lay emphasis on his teachings.
Answer:
‘Love all living things’, ‘Have mercy and compassion’, and ‘Live and let live’ are quotes that lay emphasis on his teachings.

Question 9.
Where was Gautam Buddha bom?
Answer:
Gautam Buddha was bom at Lumbini in Nepal.

Question 10.
Give the names of Gautam Buddha’s parents.
Answer:
Gautam Buddha’s father’s name was Shuddhodana and mother’s name was Mayadevi.

Question 11.
When did Gautam Buddha recieve enlightenment?
Answer:
On Vaishakha Purnima, when Gautam Buddha was sitting in deep meditation under a pipal tree at Uruvela, near the city of Gaya in Bihar, he attained ‘Bodhi’ – enlightenment or the highest knowledge.

Question 12.
Where did Gautam Buddha deliver his first sermon?
Answer:
Gautam Buddha delivered his first sermon at Samath near Vamasi.

Question 13.
In which language did Gautam Buddha preach?
Answer:
Gautam Buddha preached in the people’s language, Pali.

Question 14.
What does Pratipad mean?
Answer:
Pratipad means the ‘way’ that leads to the end of suffering.

Question 15.
What was extraordinary about Gautam Buddha’s personality?
Answer:
Compassion for all living beings was an extra ordinary feature of his personality.

Question 16.
Which religions took root in Indian society?
Answer:
Religions like Judaism, Christianity, Islam and Zoroastrianism took root in the Indian society.

Question 17.
What is a Jewish prayer house called?
Answer:
A Jewish prayer house is called a synagogue.

Question 18.
Who founded Christianity?
Answer:
Christianity is a religion founded by Jesus Christ.

Question 19.
What is the sacred book of the Christians called?
Answer:
The sacred book of the Christians is called ‘the Bible’.

Question 20.
What is the prayer house of the Christians called?
Answer:
The prayer house of the Christians is called ‘a Church’.

Question 21.
What is the holy book of Islam called?
Answer:
The holy book of Islam is called the Quran Sharif.

Question 22.
What is the prayer house of Islam called?
Answer:
The prayer house of Islam is known as a mosque or masjid.

Question 23.
What is the sacred text of Parsees called?
Answer:
The sacred text of the Parsees is the ‘Avesta’.

Question 24.
Why are the Zoroastrians called Parsees?
Answer:
The Zoroatrians came to India from the Pars or Fars province of Iran, therefore they are called as Parsees.

Question 25.
What is the name of the Zoroastrian God?
Answer:
The Zoroastrian god is called the ‘Ahur Mazda’.

Question 26.
What is the prayer house of the Zoroastrians called?
Answer:
The prayer house of the Zoroastrians is called the Agyari.

Answer in short:

Question 1.
State the principle of Tri-ratnas as taught by Vardhaman Mahavir.
Answer:
Tri-ratnas are the three jewels or the three principles taught by Vardhaman Mahavir.

• Samyak Darshan or Right faith.
• Samyak Jnati or Right knowledge.
• Samyak Charitra or Right conduct.

Question 2.
What is sangha?
Answer:

• Gautam Buddha created a sangha of Bhikkhus and Bhikkhunis to preach his religion.
• These followers where those who gave up their domestic life and entered the sangha.
• They travelled on foot like the Buddha to preach Dhamma to the people.

Question 3.
How did Gautam Buddha explain the concept of equality?
Answer:

• Gautam Buddha announced the freedom based on vama.
• He refused the discrimination based on vama.
• No one is greater or smaller by birth, says Buddha.
• He stressed that greatness depended on one’s behaviour or conduct.

Question 4.
Who came to spread Christianity to India?
Answer:

• St. Thomas, one of the twelve disciples of Christ, came to Kerala in the first century of the Christian era.
• He established a church at Pallayur in Trichur district in 52 CE.

Give reasons:

Question 1.
Why is Vardhaman said to be Mahavir?
Answer:
Vardhaman is said to be ‘Mahavir’ because he had the resilience, the courage to conquer all passions.

Question 2.
Why did Mahavir preach in Ardhamagadhi?
Answer:
Mahavir spoke in Ardhamagadhi, a people’s language, to make it easy for the people to understand his preachings.

Question 3.
Why is Buddha’s teachings termed as dhamma-chakka-pavattan?
Answer:
Buddha delivered his first sermon at Sarnath near Varanasi. His teaching in the first sermon are termed dhamma. He set in motion the wheel of dhamma in this sermon. Therefore this event is called dhamma – chakra.

Maharashtra State Board Class 6 Science Solutions Chapter 10 Force and Types of Force

Class 6 Science Chapter 10 Force and Types of Force Textbook Questions and Answers

1. Choose the term and fill in the blanks:

Question a.
……….. has to be applied to change the ……….. of a ……….. object.
(moving, direction, force)
Answer:
force, direction, moving

Question b.
When an elephant drags a wooden log over the land, the forces that are applied on the log are …………., ………. and …………. .
(muscular force, mechanical force, gravitational force, frictional force)
Answer:
muscular force, gravitationalforce, frictionalforce.

Question c.
A ball was set rolling on a large table. If its …….. has to be changed, a ……….. will have to be applied on it.
(force, motion, gravitation)
Answer:
motion, force

Question d.
The force of friction always acts ……….. the motion.
(along, against)
Answer:
against

2. Match the following:

Question a.

Answer:

3. One or more forces are acting in the following examples. Name them.

Question a.
An object falling from a tall building …………. .
Answer:
Gravitational force

Question b.
An aeroplane flying in the sky. …………. .
Answer:
Mechanical force

Question c.
Sqeezing sugarcane juice with a squeezer. …………. .
Answer:
Muscular or mechanical force

Question d.
Winnowing foodgrain …………. .
Answer:
Muscular force, gravitational force

4. Explain in your own words giving one example each.
Muscular force, gravitational force, mechanical force, electrostatic force, the force of friction and magnetic force.

Question a.
Muscular force:
Answer:
The force applied with the help of muscles is called muscular force.
e.g. When a bullock pulls the load of a cart with sugarcane, he uses the force of his muscles that is muscular force.

Question b.
Gravitational force:
Answer:
The force applied by the earth to pull the objects towards itself is called gravitational force.
e.g. When a fruit falls from a tree, it is the gravitational force of the earth that pulls the fruit.

Question c.
Mechanical force:
Answer:
The force applied by means of a machine is called mechanical force. Some machines run by muscular force while some use electricity or fuel.
e.g.Washing machine, electric pump uses electricity to work.

Question d.
Electrostatic force:
Answer:
Static electricity is produced on materials like rubber, plastic and ebonite due to friction. The force exerted by such electrically charged materials is called electrostatic force, e.g. When a plastic comb is rubbed against the dry hair, comb develops electrostatic charge.

Question e.
The force of friction:
Answer:
When two surfaces rub against each other, a force of friction is produced. This force always acts against direction of motion, e.g. A ball rolling over a flat surface stops at certain distance due to friction between the ball and the surface.

Question f.
Magnetic force:
Answer:
The force exerted by a magnet is called magnetic force.
e.g. In a pin holder, the magnet attracts the pins.

5. Why?

Question a
Machines are oiled from time to time.
Answer:
To reduce the friction between the parts of machines, they are oiled. This will help efficient working of machines.

Question b.
An object thrown upwards comes down after reaching a point.
Answer:
An object is pulled by the gravitational force of the earth. Hence an object thrown upwards comes down after reaching at certain point.

Question c.
Powder is sprinkled on a carrom board.
Answer:
When powder is sprinkled on a carrom board, friction between the coin and the board decreases so that the coin can be pocketed easily.

Question d.
The ramp at a railway station has a rough surface.
Answer:
The rough surface of the ramp increases the friction between feet and the surface. This helps us to walk on the ramp without skidding or falling.

6. In what way are we different? 

Question a.
Muscular force and Mechanical force
Answer:

Question b.
A force of friction and Gravitational force
Answer:

7. Write answers to the following questions in your own words. 

Question a.
What are the things that can be done by applying force?
Answer:
By applying force:

1. we can set an object in motion.
2. we can stop a moving object.
3. we can change the speed or direction or both of a moving object.
4. we can change the shape of an object.

Question b.
What is meant by weight?
Answer:

1. The gravitational force acting on an object is called its weight.
2. Greater force must be applied to lift a greater weight.

Question c.
Which machines run on muscular force?
Answer:
The machines that run on muscular force are:

1. Bicycle
2. Hand cart
3. Boat
4. Cycle rickshaw
5. Stretching of a spring
6. Ball pen
7. Vegetable chopper
8. Sharpener
9. Pulley
10. Fruit peeler

8. Solve the following crossword puzzle.

Question a.
Solve the following crossword puzzle.

Down:
1. ………. force is applied to push a scooter that has failed.
2. ………. force can be used to pick up scattered pins.

Across:
3. A ………. pulls iron nails towards itself.
4. ……….. force is used when farm is ploughed with a tractor.
5. It is due to the force of ………… that raindrops fall to the ground.
Answer:

Activity:

Question 1.

Collect more information about the various forces that are used in our day-to-day life.

Question 2.
Make a list of such actions where many forces are applied simultaneously.

Class 6 Science Chapter 10 Force and Types of Force Important Questions and Answers

Choose the term and fill in the blanks:

Question 1.
When powder is sprinkled on a carrom board, friction ……….. .
(increases, decreases)
Answer:
decreases

Question 2.
Electrostatic force is due to …………. .
(gravitation, friction)
Answer:
friction

Question 3.
Fruits fall on the ground due to ………… force.
(mechanical, gravitational)
Answer:
gravitational

Question 4.
Friction between two rough surfaces is …………. than between two smooth surfaces.
(greater, lesser)
Answer:
greater

Question 5.
The sound created by a stone dropped in a bucket of water from 100 cm height is ………… than that dropped from 20 cm height.
(milder, louder)
Answer:
louder

Question 6.
A scooter has stopped in the middle of the road as the petrol tank has become empty. So Raju has to use …………. force to take it to petrol pump.
(mechanical, muscular)
Answer:
muscular

One or more forces are acting in the following examples. Name them.

Question 1.
Srikant is playing basketball
Answer:
Muscular force

Question 2.
Raju rubs a peacock feather between pages of his notebook
Answer:
Electrostatic force

Question 3.
When you rub the palm of your hands, you feel the heat on the palms
Answer:
Frictional force

Question 4.
A blacksmith uses a hammer to beat the hot piece of iron
Answer:
Muscular force

Question 5.
A cricketer hits the ball, but it stops just before the boundary line
Answer:
Frictional force

Question 6.
We can walk on the road without falling down.
Answer:
Frictional force

Give scientific reasons:

Question 1.
Magnet is used to lift heavy iron bar.
Answer:
A magnet attracts the iron bar. As a result it is easier to lift the heavy iron bar using magnetic force.

Question 2.
An inflated balloon when rubbed against a silk cloth, pulls the hair on our skin.
Answer:
When an inflated balloon is rubbed against a silk cloth, it develops electrostatic force due to friction. This force pulls the hair on our skin.

Question 3.
We are likely to slip when we walk on a oily or wet floor.
Answer:
Wet or oily floor reduces the friction between our feet and surface. Hence we are likely to slip on wet or oily floor.

Distinguish between:

Question 1.
Force of friction and Electrostatic force
Answer:

Answer the following:

Question 1.
Why do planets revolve round the sun in definite orbits?
Answer:

1. The gravitational force operates between the sun and the planets in the solar system.
2. Hence, they revolve round the sun in definite orbits.

Question 2.
Which forces are acting upon an aeroplane taking off into the sky?
Answer:
Aeroplane uses mechanical force, Pilot exerts muscular force. Frictional force between aeroplane and air, gravitational force due to weight of an aeroplane.

Question 3.
What happens to the iron nail when the magnet is taken away from it?
Answer:

1. As we take the magnet away from the iron nail, it does not attract the iron nail as magnetic force decreases.
2. Magnet is unable to exert force if the nail is not placed in the range of the magnetic field.

Question 4.
When brakes are applied while riding a bicycle, it stops after running a distance. Why?
Answer:

1. When brakes are applied while riding a bicycle, frictional force comes to act between the tyres of the bicycle and the surface.
2. This force opposes the tendency of the bicycle to stop.
3. Hence, the bicycle has to overcome this force before it stops.

Can you tell?

Question 1.
What happens when you hold the two ends of a spring and pull them apart?
Answer:
Its shape changes due to the force exerted by pull.

Question 2.
What happens when a blacksmith hammers a red hot piece of iron?
Answer:
Shape of iron piece changes.

Observe and discuss:

Observe the figures given and name the force needed for the motion.

Question 1.
Boat with boatman.

Answer:
Muscular force

Question 2.
Bullock cart.

Answer:
Muscular force

Question 3.
A tractor.

Answer:
Mechanical force

Question 4.
Sewing machine.

Answer:
Mechanical force

Question 5.
Fruit falling from tree.

Answer:
Gravitational force

Question 6.
A man carrying heavy sac.

Answer:
Gravitational force

Question 7.
A pin holder.

Answer:
Magnetic force

Question 8.
A ramp.

Answer:
Gravitational force

Question 9.
Carrom board.

Answer:
Frictional force

Question 10.
Mixer grinder.

Answer:
Mechanical force

Maharashtra State Board Class 6 Science Solutions Chapter 15 Fun with Magnets

Class 6 Science Chapter 15 Fun with Magnets Textbook Questions and Answers 

1. How will you do this?

Question a.
Determine whether a material is magnetic or non-magnetic.
Answer:

1. To determine whether the material is magnetic or non-magnetic, a magnet is moved over it.
2. If the material sticks to the magnet, it is called magnetic material.
3. If the material does not stick to the magnet, it is non-magnetic.

Question b.
Explain that a magnet has a certain magnetic field.
Answer:

1. The space around a magnet in which the magnetic force is active is called the magnetic field.
2. Place a white paper on a drawing board and place a bar magnet in the middle of the paper.
3. Spread the iron filings on the sheet and gently tap the sheet.
4. The iron filings arrange around the magnet in definite curved lines forming a symmetric pattern.
5. The lines are closer to each other near the poles and less crowded in the middle region around the magnet.
6. Beyond a particular region, the iron filings, will not get attracted.
7. The region where iron filings are attracted is the magnetic field of the magnets.

Question c.
Find the north pole of a magnet.
Answer:

1. Take a bar magnet. Tie a thread to the centre of a bar magnet and hang it from a stand.
2. Note the direction in which the magnet settles and turn it around again.
3. Allow it to settle and note the direction.
4. The end of the magnet that points to the north is called the north pole, while the end that points to the south is called the south pole.
5. The north pole is indicated by ‘N’ and the south pole by ‘S’.

2. Which magnet will you use?

Question a.
Iron is to be separated from a trash.
Answer:

1. Sharp and heavy iron scrap material is attached to a big disc.
2. The disc is a magnet and all scrap is attracted to it.
3. It is not possible to create, store such a big size magnet. Therefore magnetism is induced in the disc with the help of electricity.

An electromagnet is used which is attached to a crane for loading and unloading, transporting scrap and loose iron material from a trash.

Question b.
You are lost in a forest.
Answer:

1. If we are lost in a forest, we should take help of a mariner’s compass which will help us to find the directions while travelling through unknown regions.
2. If mariner’s compass is not available, a bar magnet when suspended in the centre will rest in north-south direction.

Question c.
A window shutter opens and shuts continuously in the wind.
Answer:
A bar magnet can be attached to the window pane so that the window will be closed tight during strong winds also.

3. Fill in the blanks with appropriate word.

Question a.
If a bar magnet is hung by a thread tied at its centre, its north pole becomes steady in the direction of the …………… pole of the earth. (south, north, east, west)
Answer:
North

Question b.
If a bar magnet is cut into equal pieces by cutting it at right angles to its axis at two pieces …………… bar magnets are formed, and a total of …………… poles are formed. (6,3,2)
Answer:
3, 6

Question c.
There is a repulsion between the …………… poles of a magnet and attraction between its ……………. poles. (opposite, like.)
Answer:
like, opposite

Question d.
When magnetic material is taken close to a magnet, the material acquires …………… . (permanent magnetism, induced magnetism, temporary, magnet keeper)
Answer:
induced magnetism

Question e.
If a magnet attracts a piece of metal, that piece must be made of ………… .(any other metal but iron, magnetic material or iron, non-magnetic material, electromagnets)
Answer:
magnetic material or iron

Question f.
A magnet remains steady in a ………….. direction. (east-west, north-south,)
Answer:
north-south

4. Write the answers in your words.

Question a.
How is an electromagnet made?
Answer:
1. To make an electromagnet we need the following apparatus; An iron nail of 10 cm length, 1 metre long insulated copper wire, a battery cell, pins.
2. Wind the copper wire around the nail as shown in the figure. Connect the free ends of the wire to the two terminals of a cell through a plug key.
3. Close the key to complete the circuit.
4. Bring small pins near the tip of the nail and observe.
5. When the circuit is completed, the iron pins are attracted by the nail and hence, they stick to the nail.

6. When the circuit is broken, the pins fall off.
7. A magnet is prepared by passing an electric current through an insulated wire wound around the iron nail. This is an electromagnet.
8. When the current is allowed to pass, the nail becomes a magnet and attracts pin / pins stick to it.
9. When the current is put off the nail does not behave as a magnet and therefore, pins fall off.
10. The magnetism is temporary in the case of an electromagnet.

Question b.
Write the properties of a magnet.
Answer:
Magnet possess following properties/ characteristics.

1. Magnet always settles in the north-south direction.
2. The magnetic force is concentrated at the two ends or poles of a magnet.
3. If a magnet is divided into two parts, two independent magnets are formed. It means that the two poles of a magnet cannot be separated from each other.
4. A magnetic material acquires magnetism when placed near a magnet. This magnetism is called induced magnetism.
5. There is repulsion between like poles of a magnet, while there is attraction between the opposite poles.

Question c.
What are the practical uses of a magnet?
Answer:

1. Magnets are materials to which objects made from iron, nickel, cobalt are attracted. But man explored magnets and its properties and made his life comfortable.
2. Permanent Magnets: are used in caps of pin holders, doors of fridges, doors of cupboards etc.
3. Temporary magnets: Electromagnets are used in electric bells, circuit of various machines, ATM card swipe machines, MRI- Magnetic Resonance Image, loudspeakers, electric cranes, microphones, Mariner’s compasses, etc.

Activity

Question 1.
Collect information regarding how the various magnets used in our day-to-day tasks are produced.

Question 2.
Collect information about the magnetism of the earth.

Class 6 Science Chapter 15 Fun with Magnets Important Questions and Answers

Fill in the blanks.

Question 1.
Iron objects ………….. to a magnet.
Answer:
stick

Question 2.
A magnet is used in ………….. and ………….. .
Answer:
gadgets and machines

Question 3.
The materials that stick to a magnet are called ………….. materials.
Answer:
magnetic

Question 4.
Materials that do not stick to a magnet are called ………….. materials.
Answer:
non-magnetic

Question 5.
When a magnet attracts an object, that object is ………….. due to the magnetic force.
Answer:
displaced

Question 6.
Magnetism is a form of ………….. .
Answer:
energy

Question 7.
A magnet always settles in the ………….. direction.
Answer:
north-south

Question 8.
The north pole is indicated by’ …………… and the south pole by ‘……………’.
Answer:
‘N’-‘S’

Question 9.
The end of the magnet that points to the north is called the ………….. .
Answer:
Northpole

Question 10.
The end of the magnet that points to the south is called the ………….. .
Answer:
South pole

Question 11.
The magnetic force is concentrated at the two ends or ………….. of a magnet.
Answer:
poles

Question 12.
If a magnet is divided into two parts, two ………….. magnets are formed.
Answer:
independent

Question 13.
It means that the two poles of a magnet cannot be ………….. from each other.
Answer:
separated

Question 14.
A magnetic material acquires magnetism when placed near a
Answer:
magnet

Question 15.
Iron filling stick to the iron bar when the ………….. is near it.
Answer:
magnet

Question 16.
There is ………….. between like poles of a magnet.
Answer:
repulsion

Question 17.
There is ………….. between the opposite poles of a magnet.
Answer:
attraction

Question 18.
Magnetic objects ………….. magnetism.
Answer:
induce

Question 19.
Material ………….. is a mixture of aluminium, nickel and cobalt.
Answer:
Alnico

Question 20.
………….. magnets are made from a mixture of nickel, cobalt and iron.
Answer:
Permanent

Question 21.
The bar of soft or pure iron which protects a magnet is called ………….. .
Answer:
magnet keeper

Question 22.
Magnetism gets ………….. when a magnet is heated, thrown, knocked about or broken into pieces.
Answer:
destroyed

Question 23.
Electromagnetic energy is used in our ………….. life.
Answer:
day-to-day

Question 24.
The metals iron, cobalt, nickel are ………….. materials.
Answer:
magnetic

Question 25.
………….. is a natural magnet.
Answer:
Magnetite

Match the columns.

Question a.

Answer:

State whether true or false. If false, correct the statement.

Question 1.
Material alnico is a mixture of aluminium, nickel and iron.
Answer:
False: Material alnico is a mixture ofaluminium, nickel and cobal.

Question 2.
Magnetism of electromagnet is permanent.
Answer:
False: Magnetism of electromagnet is temporary.

Question 3.
The bar of soft or pure iron protects the magnet.
Answer:
True

Question 4.
Like poles attract each other and unlike poles repel each other.
Answer:
False: Like poles repel each other and unlike poles attract each other.

Question 5.
The magnetic force is concentrated at the centre of the magnet.
Answer:
False: The magnetic force is concentrated at the poles of the magnet

Question 6.
Magnetism is a kind of energy.
Answer:
True

Question 7.
Mariner’s compass is used for finding directions while travelling.
Answer:
True

Question 8.
Cobalt is a magnetic material.
Answer:
True

Question 9.
The north pole is indicated by ‘S’ and the south pole is indicated by ‘N’.
Answer:
False: The north pole is indicated by Wand the south pole is indicated by ‘S’.

Question 10.
Electromagnetism is used in many places in our day-to-day life.
Answer:
True

Answer the following questions in one sentence.

Question 1.
What is a magnet?
Answer:
The material to which objects made from iron, nickel, cobalt get attracted is called as magnet.

Question 2.
What is magnetism?
Answer:
The property of a material to which objects made from iron, nickel, cobalt get attracted is called as magnetism.

Question 3.
What are magnetic materials?
Answer:
Materials that stick to a magnet are called magnetic materials, e.g. cobalt, nickel, iron.

Question 4.
What are non-magnetic materials?
Answer:
Materials that do not stick to a magnet are called non-magnetic material, e.g. plastic, rubber, glass etc.

Question 5.
What are lodestones?
Answer:
Lodestones are leading stones which are used for finding the directions while travelling through unknown regions.

Question 6.
How is magnetism a kind of energy?
Answer:
Work is done by magnetic force. Thus, magnetism is a kind of energy.

Question 7.
What is an electromagnet?
Answer:
When magnetism is produced in the iron due to the electric current, it is called an electromagnet.

Question 8.
How are permanent magnets made?
Answer:
Permanent magnets are made from a mixture of nickel, cobalt and iron.

Question 9.
List the instruments where electromagnets are used.
Answer:
Electromagnets are used in doorbells, cranes, loudspeakers, voltameters, TVs, antennas, radios etc.

Question 10.
How is magnetism destroyed?
Answer:
When magnets are heated, thrown, knocked about or broken into pieces, magnetism gets destroyed.

Question 11.
What is a magnet keeper?
Answer:
A magnet keeper is a bar of soft or pure iron which protects a magnet. It is a piece of soft iron placed in the box in which a magnet is kept.

Question 12.
Magnets exist in variety of shapes.
Answer:
Today, magnets are used in many machines, gadgets and devices. They are all man-made. Hence, they can have a variety of shapes depending upon their use.

Answer the following briefly.

Question 1.
What are leading stones?
Answer:

1. It was known quite long ago to the people in China and Europe that a piece of magnetite, hung freely always settled in the north-south direction.
2. These rocks then came to be used for finding the directions while travelling through unknown regions.
3. That is why they are called leading stones or Lodestones.

Question 2.
What has led to the invention of the Mariner’s compass?
Answer:
Leading stones have led to the invention of the mariner’s compass.

Question 3.
List the different shapes of magnets.
Answer:

1. Magnets have a variety of shapes depending on their uses.
2. They are bar magnets, disc magnets, horseshoe magnets, ring shaped magnets, cylindrical magnets, and small button magnets.

Question 4.
What are permanent magnets?
Answer:

1. Magnets which do not lose their magnetism easily are called permanent magnets or Magnets which are made up of magnetic substances are permanent magnets.
2. e.g. Magnets fixed in a pin holder, magnets of a door of a cupboard are permanent magnets.
3. Permanent magnets are made from a mixture of
   • Nickel, cobalt, iron
   • Aluminium, nickel, cobalt – alnico

Give scientific reasons.

Question 1.
Why is it important to place a magnet keeper in a box along with magnets?
Answer:
Magnetism gets destroyed when a magnet is heated, thrown, knocked about or broken into pieces. A magnet keeper which is a bar of soft or pure iron protects a magnet.

Question 2.
Cranes with magnets are used.
Answer:
When a magnet attracts an object, that object is displaced due to the magnetic force. In factories, ports, garbage depots, large objects are lifted and shifted from place to place using cames. Hence cranes are fitted with magnets.

Can you tell?

Question 1.
Pins in a pin holder do not fall? While we are shutting the door of a fridge, we find that it closes automatically from certain distance and does not open unless pulled again.
Answer:
Magnet is fitted in the cap of a pin holder and in the door of a fridge. Iron objects stick to the magnet.

Question 2.
Take a magnet from the laboratory and bring it near various objects in your use. Which of them stick to the magnet? What material is each of them made of? Observe these things carefully. Classify the objects into two groups: those which stick to the magnet, those which do not.
Comb, table, cupboard – iron, spoon, scissors, pen, pencil, eraser, books, mobile, laptops, glass bangles, hair pin, cupboard handle, chair, steel lunch box, magnetic stickers, toys, gold ring.
Answer:

Question 3.
Take a mixture of sand, pieces of paper, sawdust, iron filings and pins in a saucer and pass a magnet around the mixture. What do you see?
Answer:
When magnet is moved over a mixture of sand, pieces of paper, sawdust, iron filings and pins, pins and iron filings will cling to the magnet. Sand, sawdust and pieces of paper will remain behind.

Question 4.
How is a Mariner’s Compass used?
Answer:

1. A Mariner’s Compass is a magnetic needle used in navigation to show direction by deflections.
2. It is a direction-finding instrument used in navigation.
3. It is placed on the maps, grounds, decks as it will point to the magnetic north pole.
4. It has two or more magnets permanently attached to a compass card which moves freely on a pivot.
5. The needle fixed on the compass bowl indicates the ship’s heading position.

Question 5.
Find out where the magnet given are used?
Answer:

Question 6.
Identify the different types of magnets as shown in the picture below.
Answer:
a. Circular magnet
b. Cylindrical magnet
c. Horseshoe magnet
d. Bar magnet

Maharashtra State Board Class 6 Science Solutions Chapter 9 Motion and Types of Motion

Class 6 Science Chapter 9 Motion and Types of Motion Textbook Questions and Answers

1. Identify the types of motion.

Question a.
Movement of the earth around the sun: …………… .
Answer:
periodic, drcular

Question b.
Movement of ceiling fan: …………… .
Answer:
circular

Question c.
A rocket launched from the ground: ……….. .
Answer:
linear

Question d.
A fish swimming in water: ……… .
Answer:
random

Question e.
The plucked string of a sitar:………….. .
Answer:
oscillatory motion

2. Fill in the blanks.
(linear, non-linear, uniform linear, non-uniform linear, uniform circular, random, circular, non-uniform circular)

Question a.
If a ball is released from the terrace of a building, it comes down in ………… motion. On the other hand, it reaches the ground in ………… motion if it is thrown with a force away from the terrace in a direction parallel to the terrace.
Answer:
uniform linear, non-uniform linear

Question b.
The motion of an aeroplane on the runway before take off is …………. .
Answer:
linear

Question c.
The kite looking for its prey flies with …………. motion in the sky.
Answer:
circular

Question d.
Children sitting in a rotating giant wheel have ………. motion, while those sitting in a merry-go-round have a ………. motion.
Answer:
uniform circular, non-uniform circular

3. How are we different?.

Question a.
Oscillatory motion and Linear motion.
Answer:

Question b.
Linear motion and Random motion
Answer:

Question c.
Random motion and Oscillatory motion
Answer:

4. Explain in your own words, giving one example each.

Question a.
Linear motion
Answer:
An object that shows displacement along a straight line is called linear motion, e.g. A vehicle moving on a road.

Question b.
Oscillatory motion
Answer:
The motion of a body swinging back and forth is called oscillatory motion, e.g. Motion of a pendulum of a clock.

Question c.
Circular motion
Answer:
The motion of an object along a circular path is called circular motion, e.g. Motion of a ceiling fan.

Question d.
Random motion
Answer:
The motion that changes its direction and speed continuously is called random motion, e.g. Motion of a butterfly.

Question e.
Periodic motion
Answer:
The repetitive motion in which the moving object passes through a certain point again and again after a fixed period is called as periodic motion, e.g. The minute hand of a clock.

5. Answer the following questions in your own words. 

Question a.
Which types of motion are seen in birds flying in the sky?
Answer:

1. The birds flying in the sky exhibit random motion.
2. The wings of the birds show oscillatory motion.

Question b.
Write in detail about your experience of various types of motion while riding a bicycle on a road.
Answer:

1. The cycle itself shows linear motion.
2. The wheels of the cycle show circular motion.
3. The cycle chain shows periodic motion, if the speed is uniform.
4. The handle bar shows random motion.

6. Complete the puzzle using words for types of motion: 

Question a.
Complete the puzzle using the words for types of motion.
1. A spring is stretched and one end is released.
2. A minute hand.
3. A see-saw.
4-5.  Children in a march past.
6. A stone rolling down a hillside.

Answer:

1. Oscillatory
2. Circular
3. Periodic
4. Uniform
5. Linear
6. Random

Activity:

Question 1.
Make a list of various moving objects in the environment, and discuss the types of motion seen in them.

Class 6 Science Chapter 9 Motion and Types of Motion Important Questions and Answers

Identify the types of motion.

Question 1.
The movement of a see-saw.
Answer:
oscillatory motion

Question 2.
The motion of a moving ant.
Answer:
random

Question 3.
The marching army soldiers.
Answer:
linear

Question 4.
A train approaching a station.
Answer:
non-uniform linear

Question 5.
A meteor falling from the sky.
Answer:
linear

Fill in the blanks with suitable words from those given in the bracket:
(linear, non-linear, uniform linear, non-uniform linear, uniform circular, random, circular, non-uniform circular)

Question 1.
The motion that changes its speed and direction continuously is called ………. .
Answer:
random

Choose the correct alternative:

Question 1.
A baby is crawling. The motion is said to be …………….. .
(a) linear
(b) periodic
(c) circular
(d) random
Answer:
(d) random

Question 2.
The children are having a 50m running race. The motion exhibited is ………….. motion.
(a) linear
(b) periodic
(c) random
(d) circular
Answer:
(a) linear

Question 3.
The motions of the hands of a clock are ………….. and …………. .
(a) periodic, linear
(b) periodic, circular
(c) non-linear, non-uniform
(d) circular, non-uniform
Answer:
(b) periodic, circular

Question 4.
The motion of a pendulum of a clock is ……………. .
(a) linear
(b) oscillatory
(c) circular
(d) random
Answer:
(b) oscillatory

Question 5.
The motion of a butterfly from one flower to another flower is an example of …………… motion.
(a) circular
(b) periodic
(c) linear
(d) random
Answer:
(d) random

Question 6.
The distance traversed by an object in a unit time is called ……….. of that object.
(a) length
(b) motion
(c) speed
(d) displacement
Answer:
(c) speed

Explain it in your own words, giving one example of each.

Question 1.
Uniform linear motion
Answer:
When the distance traversed by an object along a straight line in unit time is the same, the motion is called as uniform linear motion, e.g. Motion of soldiers on parade.

Question 2.
Non-uniform linear motion
Answer:
When the distance traversed by an object along a straight line in unit time keeps on changing, the motion is called non-uniform linear motion.
e.g. A girl coming down a slide.

Question 3.
Non-linear motion
Answer:
The motion of an object that does not move in a straight line is called non-linear motion.
e.g. Motion of a swing,

Question 4.
Speed
Answer:
The distance traversed by an object in unit time is called the speed of that object.
e.g. A boy riding on a bicycle covers a distance of 15 kilometres in 3 hours.
Hence Speed = \(\frac{15}{3}\) = 5 kilometres/hour

Answer the following:

Question 1.
In which muscial instruments can you see oscillatory motion?
Answer:
Vibrating diaphragm of tabla, drum, dhol and strings of sitar, guitar show oscillatory motions.

Question 2.
With reference to types of motion, complete the table below.

Answer:

1. Non-linear
2. Uniform
3. Oscillatory
4. Periodic
5. Random.

Read the following stories and answer the questions.

Rita and Geetha are friends travelling from Mumbai to Pune. Seetha had come to the station to see her friends off. After 15 minutes train starts moving. Rita and Geetha feel that Seetha and the vendors on platform are moving backwards. Whereas, Seetha feels that Rita and Geetha are moving forward. Rita feels Geetha is not in motion and Geetha also feels Rita is not in motion. Can you say why?

Question a.
Are Rita and Geetha in motion?
Answer:
Rita and Geetha are not in motion as far as each other are concerned, as no displacement takes place. Both are in a train. For Seetha, both of them are in motion.

Question b.
Are the vendors and Seetha in motion?
Answer:
No, the vendors and Seetha are not in motion. But Rita and Geetha feel as if they are moving backwards.

Question c.
What can you conclude from this passage?
Answer:
An object which is in motion for one person may not be in motion for another. This shows that motion is relative.

Observe and discuss:

Question 1.
Observe the figure and classify the type of motion.


Answer:

1. Circular motion
2. Linear motion
3. Circular motion
4. Linear motion
5. Oscillatory motion
6. Oscillatory motion
7. Circular motion
8. Circular motion
9. Bird – Random; Wings – Oscillatory motion
10. Circular motion
11. Linear, circular

Can you tell?

Question 1.
While chasing a butterfly in a garden, do you run along a definite path or in the same direction all the time?
Answer:
No, we move in random motion.