Question bank

Chapter-1   Matter
Q-1

Fill in the blanks.
(1) The change of state from solid to liquid at fixed temperature is called ____________.
(2) When a liquid freezes the kinetic energy of its molecules ____________.
(3) Properties of compressibility and fluidity is present in ____________.
(4) The space between two molecules is called ____________.
(5) In gases the intermolecular attraction is ____________.
(6) When water changes from liquid to vapour state its volume ____________.
(7) In deposition the state of the substance will ____________.
(8) On a windy day evaporation from a pond will ____________.
(9) Frost formation on leaves is an example of ____________.
(10) When change of state is happening the kinetic energy of the system ____________.
Q-2

Short answer type questions.
(1) What is Brownian movement?
(2) Why solids cannot be compressed?
(3) Compare intermolecular space of solids and liquids.
(4) Why gases are easily compressed?
(5) What is the force of adhesion?
(6) Why by hammering only, we can break a stone?
(7) Define evaporation.
(8) Give an example of sublimation.
(9) Why gases occupy all the available space?
(10) How kinetic energy of a liquid changes upon heating?
Q-3

Long answer type questions.
(1) Compare intermolecular attraction in three states of matter.
(2) How can we prove that matter is made of numerous small particles?
(3) What forces are responsible for vibration of particles in solids?
(4) What are conditions that affect evaporation?
(5) Explain freezing from the point of view of kinetic theory of matter.
(6) Differentiate between solids, liquids and gases on any three parameters.
(7) What are the changes on the parameters of kinetic theory during evaporation?
(8) Explain the molecular model of liquids.
(9) How does heating an ice cube affect its molecular makeup?
(10) Why upon heating do gases expand much more than solids and liquids?
Q-4 Match the column (Physical changes with the correct description)
Q-5

State True or False and correct the false statement.
(1) When sugar dissolves in water, it actually lies on water particles.
(2) Matter is made of small particles fused as a block.
(3) Evaporation causes cooling.
(4) Liquids do not have a regular arrangement of particles.
(5) On heating kinetic energy of particles always increases.
(6) On heating solids can expand more than its liquid state.
(7) The force of intermolecular attraction is not affected by heating.
(8) When camphor vaporises it is called sublimation.
(9) Intermolecular attraction is directly proportional to intermolecular space.
(10) When average kinetic energy of a substance is very high its temperature must be quite low.
Multiple Choice Questions
Q-1 In Brownian movement the movement happens in :

(i)

The container in which the liquid is kept

(ii)

The particles in a solid

(iii)

The particles of gases only

(iv)

The particles in the fluid

Q-2 Solids and liquids :

(i)

Have fixed shape

(ii)

Have fixed volume

(iii)

Cannot flow

(iv)

Cannot flow
Q-3 When condensation happens –

(i)

The volume of the substance in the gaseous state increases.

(ii)

The attraction between the particles increases.

(iii)

The particles begin to repel each other vigorously.

(iv)

The volume of the substance in the gaseous state decreases.

Q-4 According to the Kinetic theory of matter –

(i)

Matter occupies space

(ii)

Matter occupies space

(iii)

Matter is made of tiny particles which move

(iv)

Matter can be created or destroyed
Q-5 Liquids have a fixed volume because –

(i)

The intermolecular space is small

(ii)

The intermolecular space is large

(iii)

The intermolecular force of attraction is less than gases

(iv)

The intermolecular force of attraction is more than gases

Q-6 Our clothes dry in winter because –

(i)

of condensation

(ii)

of evaporation

(iii)

of Brownian movement

(iv)

of vaporization

Q-7 In case of water the cohesive force is

(i)

stronger than adhesive force of glass

(ii)

weaker than the adhesive force of glass

(iii)

same as adhesive force of glass

(iv)

Non existent
Q-8 Which of the following sentences is correct for boiling?

(i)

Boiling takes place at the bottom of the liquid.

(ii)

In boiling the kinetic energy of all the particle is the same.

(iii)

Boiling takes place only at the surface of the liquid

(iv)

In boiling kinetic energy of the particles is high at the surface.
Q-9 When a substance cools down –

(i)

the intermolecular spaces increase

(ii)

the intermolecular attraction decreases

(iii)

the volume of the substance can decrease

(iv)

the volume of the substance can increase
Q-10 Which of the following factors does not affect evaporation of water?

(i)

Extent of surface area

(ii)

Wind speed

(iii)

Surrounding temperature

(iv)

Insoluble impurities.

Chapter-2   Physical Quantities and Measurement
Q-1 State True or False and correct the false statement giving reasons
(1) As per S.I. system the unit of density is kg m-3.
(2) Mass of an irregular body can be measured by a spring balance.
(3) The zero marking in a measuring cylinder is in the middle.
(4) Density of only regular solids = Mass/Volume.
(5) Up-thrust happens to a body because its lower surface is at greater depth.
(6) Iron ball floats in mercury because density of iron is high.
(7) A brick weighs more in water than in air.
(8) Ice floats in water because density of water is less.
(9) Rules of floatation don’t apply to gases.
(10) When a liquid cools down its density increases.
Q-2 Fill in the blanks
(1) Density bottles have a fixed ____________.
(2) When a ball weighs A, in air and B, in water, it’s up-thrust will be ____________.
(3) Density of irregular solids = Mass / ____________.
(4) When a solid substance melts its density ____________.
(5) If a body has sunk in a liquid it means it’s up-thrust is ____________.
(6) If potato floats in water its density should be ____________.
(7) Buoyancy experienced by an iron ball in water is ____________ than in mercury.
(8) If a body has sunk in water its density must be ____________ than water.
(9) It is easier to swim in the sea because it is ____________.
(10) Relative density of iron is 7.5, it indicates it is ____________ denser than water.
Q-3 Short answer type questions
(1) What is the density of a substance?
(2) Why is up-thrust so called?
(3) Describe usefulness of a density bottle.
(4) How do submarines sink and come back to the surface of the sea?
(5) How can we identify a material by knowing its density?
(6) In calculating the volume of a body when do we use a sinker?
(7) Among the three states of matter which has the lowest density?
(8) By composition the ice and water are the same; yet why does ice float in water?
(9) Why does an egg float in salt-water but not in tap water?
(10) Will a body experience the same buoyancy in water and mustard oil?
Q-4 Long answer type questions
(1) How can we calculate density of potato? Explain the steps.
(2) Name the factors on which the floating ability of a body depends.
(3) If a body sinks in water, is its apparent weight in water still less than its weight in air? Explain.
(4) Why is it easier for us to swim in the sea than in the river?
(5) Explain how a ship floats in water but an iron nail sinks.
(6) What is the connection between density and relative density?
(7) Why do certain objects float in water while others do not?
(8) Up thrust depends on the difference in forces acting on the upper and the lower surface of a body. Explain.
(9) Explain why force of buoyancy is more in mercury than in water for the same iron ball?
Q-5 Match the column
Multiple Choice Questions
Q-1 When two bodies having same mass but have different density:

(i)

They will have the same volume

(ii)

Body having higher density will have greater volume

(iii)

Body having lower density will have greater volume

(iv)

Body having lower density will have lesser volume
Q-2 When volume of two substances of different density are the same :

(i)

Their mass will also be the same

(ii)

The mass of substance with higher density will be more

(iii)

The mass of substance with lower density will be high

(iv)

The mass of substance with lower density will be more

Q-3 When a body is immersed in a liquid; which of the following is not a correct statement about buoyancy?

(i)

It is equal to loss of weight of a body in the liquid.

(ii)

It is equal to the weight of the displaced fluid.

(iii)

It is the final weight of body in the fluid.

(iv)

It is the weight of body in air minus weight of the body in fluid.
Q-4 Density of water is maximum at:

(i)

Zero degree Celsius

(ii)

Hundred degree Celsius

(iii)

Four degree Celsius

(iv)

Thirty degree Celsius
Q-5 The unit of relative density is :

(i)

g/cm3

(ii)

kg/cm3

(iii)

kg/m3

(iv)

None of the above

Q-6 When a body is immersed in a liquid the up-thrust depends upon:

(i)

Weight of the displaced liquid

(ii)

Weight of the body

(iii)

Density of the body

(iv)

Volume of the liquid in the container
Q-7 We can calculate the density of a substance soluble in water by

(i)

dissolving it

(ii)

by keeping it in plastic pouch

(iii)

by using a liquid in which it is insoluble

(iv)

By using another substance of the same volume
Q-8 If two metal cubes A and B, having same volume have density in the ratio of 2:1. Which metal cube will have more up thrust on getting immersed completely?

(i)

Cube A

(ii)

Cube B

(iii)

Same for both the cubes

(iv)

Cannot be determined
Q-9 Which of the following statement is correct?

(i)

Balloons of same volume filled with air or hydrogen will have same up-thrust.

(ii)

Balloon filled with air will have more up-thrust because air is denser.

(iii)

Balloon filled with hydrogen will have more up-thrust that is why it rises.

(iv)

There is no up-thrust for balloons in atmosphere.
Q-10 If the weight of a body Fg acting vertically downwards is equal to Fb the buoyant force acting vertically upwards or (Fg=Fb) the body will-

(i)

Sink to the bottom

(ii)

Float on the surface of the liquid

(iii)

It will keep moving between the top and the bottom to the liquid

(iv)

Stay stable beneath the surface of the liquid

Chapter-3   Force and Pressure
Q-1 State True or False and correct the false statement giving reasons
(1) Turning forces create translatory motion.
(2) In a reservoir water exerts pressure only at the bottom.
(3) The turning effect of a force about a pivot is called moment.
(4) A long handle spanner is useful in opening a tight nut.
(5) Pressure created on the ground by a brick is the same when placed on any of its faces.
(6) When the distance of force from the pivot is more, moment also is more.
(7) When the surface area is increased the pressure also increases.
(8) Feet of camels create high pressure on the desert sand.
(9) The only reason for low air pressure on hills is that there is less pollution.
(10) When you are standing the pressure created on the floor is more.
Q-2 Fill in the blanks
(1) Usually the door handles are fitted at ____________ end of the door.
(2) The components of moment of force are ____________ and ____________.
(3) Higher we go ____________ is the air pressure.
(4) Unit of moment of force is ____________.
(5) Thrust acts ____________ on a surface.
(6) Pressure exerted by a liquid at a depth is same in ____________.
(7) Deep sea divers wear special suits as a protection from ____________.
(8) Moment arm is the ____________ between the pivot and the line of action.
(9) Pressure exerted by atmosphere comes from ____________ of air above us.
(10) There are breathing holes in the petrol tank Lids because ____________.
Q-3 Short answer type questions
(1) What is moment of force?
(2) How does increase of area affect pressure?
(3) What are the units of thrust and pressure?
(4) Why sleepers are put under the rail tracts?
(5) Why do sharp pins work better than blunt pins?
(6) How can you increase pressure when the thrust is low?
(7) Why deep sea divers wear special suits?
(8) How does atmospheric pressure differ on hills from plains?
(9) Can you explain how you are able to drink from a straw?
Q-4 Long answer type questions
(1) What are clockwise and anticlockwise moments?
(2) Explain by describing an experiment that proves that there is atmospheric pressure around us.
(3) What is the relation between thrust, area and pressure?
(4) If you have to design a door of heavy wood, why would you want to make it wider?
(5) Why shoes with pointed heels create deeper impact on soft soil?
(6) Name the factors upon which pressure in liquids depend.
(7) What are the similarities between pressure created by water and air.
(8) Why are the foundations of high rise buildings made broader?
(9) Give two practical application of our understanding about liquid pressure.
Q-5 Match the column
Multiple Choice Questions
Q-1 Rotating a body is easy when the force is applied :

(i)

At the pivot

(ii)

Close to the pivot

(iii)

Far from the pivot

(iv)

Anywhere on the body
Q-2 The SI unit of moment of force is :

(i)

Pascal (Pa)

(ii)

Newton (N)

(iii)

Newton meter

(iv)

dyne
Q-3 Thrust can be defined as :

(i)

Force acting on a body

(ii)

Force acting perpendicularly on a surface

(iii)

Force acting on a unit area

(iv)

Force acting tangentially on a body
Q-4 Pressure and thrust are related as:

(i)

Pressure = 1/ Thrust

(ii)

Pressure = Area X Thrust

(iii)

Pressure = Area / Thrust

(iv)

Pressure =Thrust /Area
Q-5 When a thrust is acting on a surface pressure will increase if :

(i)

Area of application increases

(ii)

Thrust acts perpendicularly

(iii)

Area of application decreases

(iv)

Area of application is made smooth
Q-6 Which of the following statements about atmospheric pressure is correct?

(i)

Atmospheric pressure on the hills is less because they have low temperature.

(ii)

Atmospheric pressure at sea level is high because the sea is a very large water body.

(iii)

Atmospheric pressure above our head depends on the column of air above it.

(iv)

Atmospheric pressure of place is higher at night.
Q-7 Which of the following is true for pressure exerted by liquids?

(i)

Pressure remains the same as we go deeper in the sea.

(ii)

Pressure decreases as we go deep in the sea.

(iii)

At the same depth pressure is same in all direction.

(iv)

There is no pressure exerted by liquids in upward direction.
Q-8 Battle tanks have special caterpillar wheels because :

(i)

So that they don’t have a tire puncture in the war situation.

(ii)

These wheels are much stronger than other types of wheels.

(iii)

To spread the heavy load over larger area so the wheels don’t sink.

(iv)

They reduce the weight of the tanks and improve fuel efficiency.
Q-9 Pressure in liquids depends upon :

(i)

Density and height of the liquid column above the point of measurement

(ii)

Density and depth of the liquid below the point of measurement.

(iii)

Density and the depth at which the liquid is kept compared to the sea level.

(iv)

Density and the volume of the liquid used in the measurement.
Q-10 Which of the following explains the working principle of rubber sucker hooks?

(i)

They are made of light material like plastics which stick to walls.

(ii)

High pressure is created inside the cup so they stick to the walls.

(iii)

The cups create a vacuum and then they are pressed to the walls by air pressure.

(iv)

Rubber sucker hooks can be fixed anywhere with the help of their hooks.
Chapter-4   Energy
Q-1 State True or False and correct the false statement giving reasons
(1) If one gets tired that means work is done.
(2) The SI unit of work is watt.
(3) A porter walking with luggage on his head does work.
(4) A moving body can have only kinetic energy.
(5) Potential energy depends on mass and height attained.
(6) A 20 watt bulb consumes 20 joule of energy every second.
(7) When mass of a body doubles its kinetic energy becomes four times.
(8) Potential energy usually changes to kinetic energy when it is put to use.
(9) In a candle mechanical energy changes to light energy.
(10) In the production of hydroelectricity kinetic energy of water is used.
Q-2 Fill in the blanks
(1) Work is ____________ when there is no motion.
(2) Work done is force multiplied by ____________.
(3) S I, unit of work done is ____________.
(4) S I, unit of energy is ____________.
(5) When speed of a projectile doubles the kinetic energy becomes ____________.
(6) In a toaster electrical energy changes to ____________.
(7) Coiled spring in a mechanical watch has ____________ energy.
(8) Mechanical energy is composed of KE and ____________.
(9) Power can be defined as amount of energy consumed ____________.
(10) One Horse power is equal to ____________.
Q-3 Short answer type questions
(1) On which factors does work done depend?
(2) What is one joule of work done?
(3) How do we define energy?
(4) What is the relationship between work and energy?
(5) Give an example of elastic energy.
(6) In transformation of energy some energy is always lost. Give an example.
(7) What is the change in energy status as a child slides down a slider?
(8) What effect increased height has on gravitational potential energy?
(9) When there is no motion, what kind of energy can a body have?
(10) What kind of energy a fired bullet has?
Q-4 Long answer type questions
(1) Explain the concept of work done in physics.
(2) What are the factors on which potential energy of a body depends, explain with an example?
(3) Differentiate between a person carrying a luggage on the head and another person dragging his luggage while walking.
(4) What are the factors affecting Kinetic energy?
(5) Taking the example of a simple pendulum, explain transfer of energy between the ends of its amplitude.
(6) Whenever mechanical energy changes to other forms of energy; it first changes to kinetic energy. Explain.
(7) Kinetic energy can easily change to any form of energy. Explain giving examples.
(8) Differentiate between power and energy.
(9) What is the difference between work and power?
(10) Calculate the potential energy of a 4 kg rock that you have lifted to the top of a hill 100 m high. Take acceleration due to gravity (g) as 10 m/sec2.
Q-5 Match the column
Multiple Choice Questions
Q-1 We can say work is done only when :

(i)

We do hard work and exert ourselves, as before an examination.

(ii)

We get tired and want to take rest, to regain the energy levels.

(iii)

On application of force the body moves in the direction of the force.

(iv)

Large amounts of energy is consumed and one feels exhausted.
Q-2 Which of the following statements explain a situation when work is not done:

(i)

The movement is perpendicular to the direction of application of force.

(ii)

There is movement along the hill but against the gravity.

(iii)

There is movement down the hill in the direction of the gravity.

(iv)

Compressing an air filled balloon so as to reduce its volume.
Q-3 In a situation when the moving body comes back at the starting point:

(i)

work is not done because there is no expenditure of energy.

(ii)

work is not done because there is no net displacement.

(iii)

work is done because there is movement.

(iv)

work is done because energy is spent by the moving body.
Q-4 An example of kinetic energy is :

(i)

Energy possessed in a rock on the top of a table.

(ii)

Energy in a stretched rubber band.

(iii)

Energy in a sleeping person after a protein rich meal.

(iv)

Energy in a flying projectile before it reaches its destination.

Q-5 When the speed of a moving object doubles its kinetic energy will:

(i)

Will also double

(ii)

Will become half

(iii)

Will become one fourth

(iv)

Will become four times

Q-6 When the height of an object doubles its potential energy

(i)

Becomes half

(ii)

Becomes double

(iii)

Remains the same

(iv)

Becomes four times
Q-7 For a falling body which of the following statement is correct:

(i)

Kinetic energy keeps decreasing

(ii)

Potential energy keeps increasing

(iii)

Kinetic energy keeps increasing

(iv)

Potential energy does not change
Q-8 The only form of energy a body at rest can have is :

(i)

Zero

(ii)

Kinetic energy

(iii)

Potential energy

(iv)

Resting energy
Chapter-5   Light Energy
Q-1 State True or False and correct the false statement giving reasons
(1) Light travelling from air to water will always change direction.
(2) Physical density and optical density are the same thing.
(3) Speed of only violet light is reduced when passing through a glass slab.
(4) A pencil dipped in water appears bent in the middle because of refraction.
(5) The value of μ, for a particular colour of light is constant.
(6) The geometric centre of a curved mirror is its focus.
(7) A convex mirror is also called the divergent mirror.
(8) Rays from a bulb placed at focus of a concave mirror is reflected as parallel rays.
(9) A convex mirror can be conveniently used as shaving mirror.
(10) Convex mirrors are divergent because they have low focal length.
Q-2 Fill in the blanks
(1) If a ray passes from air to glass without deviation, it must be ____________ to the surface of glass.
(2) The angle of incidence is formed between the incident ray and ____________.
(3) Splitting of sunlight into its component colours is ____________.
(4) Glass is optically ____________ than air.
(5) By convention in a ray diagram the dotted lines are used for ____________.
(6) A ray of light passing through ____________ in a concave mirror retraces its path.
(7) A real image will always be ____________.
(8) Focal length of a convex mirror is half of the ____________.
(9) If an image is formed behind the mirror it must be ____________.
(10) The mirror used as street light reflectors are ____________.
Q-3 Short answer type questions
1. Define the following: a) Centre of curvature of a curved mirror. b) Focal length of a concave mirror. c) Principal axis of a curved mirror
2. How can we calculate refractive index of a medium?
3. What is refraction of light?
4. What are angle of incidence and angle of refraction?
5. Draw a ray diagram, showing how a swimming pool appears shallower than it is?
6. What is a mirage?
7. What is a convergent lens?
8. State two properties of a real image.
9. Explain conjugate foci with the help of an example.
10. What are the properties of a virtual image?
Q-4 Long answer type questions
(1) Why do the stars twinkle at night while the planets do not ?
(2) Why do we see the Sun, even after it has actually set beyond the horizon?
(3) Explain dispersion of white light through a prism with the help of a diagram.
(4) Explain how speed of light helps us to calculate refractive index of a medium?
(5) In making ray diagrams, which are the standard rules we must follow?
(6) In the study of reflection through curved mirror, what are convenient rays?
(7) What is meant by focus and focal length of a concave mirror; explain with the help of a diagram.
(8) How can we differentiate between concave and convex mirrors?
(9) What are the differences between an image formed by a plane mirror and a concave mirror with object at infinity?
(10) Why convex mirrors are preferred over plane mirrors as rear-view mirrors in vehicles?
Q-5 Match the column
Multiple Choice Questions
Q-1 If the angle of incidence for light travelling from air in to a glass slab is 60 ° and the angle of refraction is 38.7 ° what would be the refractive index of that glass slab?

(i)

1.25

(ii)

23.22

(iii)

21.30

(iv)

1.55

Q-2 When travelling through a prism splitting of white light happens because :

(i)

Speed of light in glass is less than what it is in vacuum.

(ii)

The components of light break free from each other and part ways.

(iii)

a and c both

(iv)

Speed of the component lights have different speed in glass.

Q-3 When the speed of light in a transparent medium is less:

(i)

Its density must be low.

(ii)

Its optical density must be low.

(iii)

Its optical density must be high.

(iv)

The material must be a liquid.
Q-4 When the angle of refraction is more than the angle of incidence:

(i)

Light is travelling from rarer medium to denser medium.

(ii)

Light is travelling from denser medium to rarer medium.

(iii)

The speed of light is reduced in the second medium.

(iv)

The speed of light remains unchanged in both the media.
Q-5 Stars twinkle in the night because:

(i)

Their light is reflected from the sky multiple times leading to the twinkle.

(ii)

Light from heavenly bodies undergo reflection through layers of the air.

(iii)

Stars behave as point source of light that undergoes refraction through layers of the air.

(iv)

Heavenly bodies twinkle at night because of their rotation on their axes.
Q-6 Which of the following statements is correct about focal length and pole of a curved mirror?

(i)

The focal length is twice the length of the centre of curvature.

(ii)

Distance between the pole and the focus is called focal length.

(iii)

A ray passing through the focus retraces its own path.

(iv)

In a curved mirror the pole and the focus are on different plane.
Q-7 The correct reason for formation of an image by a spherical mirror is :

(i)

Refraction of light from the object

(ii)

Light rays emanating from an object on the principal axis

(iii)

Meeting of at least two reflected ray from the mirror

(iv)

Light travelling at its optimum speed after reflection.
Q-8 When a beam of light from a very far-off source strikes a concave mirror;

(i)

The image formed is erect, real and enlarged.

(ii)

The image formed is inverted, highly enlarged.

(iii)

The image formed is inverted and highly diminished.

(iv)

The image formed is virtual and cannot be put on a screen.
Q-9 Which of the following is a correct use of a convex mirror?

(i)

As a shaving mirror

(ii)

As a rear-view mirror in a car

(iii)

As a reflector in a torch

(iv)

As a reflector in a solar cooker
Q-10 Which of the following is a proof that an image is real?

(i)

It is larger than the object.

(ii)

It can obtained on a screen.

(iii)

It is formed behind the mirror.

(iv)

It is always erect.
Chapter-6   Heat Transfer
Q-1 State True or False and correct the false statement giving reasons
(1) The process that dries clothes in the Sun is called superficial expansion.
(2) Condensation can happen at any temperature.
(3) Evaporation happens only from the surface of a liquid.
(4) On heating, glass expands more than steel.
(5) In bimetallic strip the curve happens on the side of metal with lower expansion.
(6) Temperature remains constant as long as boiling happens.
(7) The density of a liquid at higher temperature will be more.
(8) The expansion in liquids is of superficial type.
Q-2 Fill in the blanks
(1) A reason for increased evaporation of liquid at room temperature is increase of ____________.
(2) The process of boiling happens at ____________.
(3) Change of state from gaseous to solid state is called ____________.
(4) In a pressure cooker water boils at ____________ temperature.
(5) In thermal expansion the space between the molecules ____________.
(6) Superficial expansion is the increase in ____________.
(7) Kinetic energy of hot objects is always ____________.
(8) The density of water is maximum at ____________.
(9) Mercury is used in thermometers because it has a ____________ expansion.
(10) Liquids expand ____________ than gases.
Q-3 Short answer type questions
(1) Why evaporation produces cooling?
(2) Name three factors that affect evaporation?
(3) How does the density of a solid change when its temperature falls?
(4) When ice melts what is the change in its volume?
(5) What is coefficient of linear expansion of solids?
(6) What is the reason for sagging of electrical cables in summer?
(7) Why do railway lines have gaps have gaps between them?
(8) Why liquids and gases do not have linear expansion?
(9) Name a practical application of thermal expansion of liquids.
(10) Water boils at lower temperature at hill stations, how does it affect cooking?
Q-4 Long answer type questions
(1) How kinetic theory explains evaporation?
(2) Give three differences between evaporation and boiling.
(3) What are the factors that affect the linear expansion of solids?
(4) Name three types of expansion in solids and the relationship between them?
(5) Explain the functioning of a bimetallic strip.
(6) Explain the factors on which volume expansion of a metal ball depends?
(7) Temperature of a boiling liquid does not change, so why will its temperature change if heating is stopped?
(8) How can you prove that different liquids have different coefficient of expansion?
(9) Explain why substances expand upon heating?
(10) Explain why liquids and gases have greater thermal expansion than solids.
Q-5 Match the column
A                                                                                         B 1. Sublimation                                                      (a) Gas to solid 2. Vaporization                                                     (b) Gas to liquid3. Deposition                                                        (c) Solid to gas 4. Condensation                                                  (d) Solid to liquid 5. Melting                                                              (e) Liquid to gas 6. Freezing                                                            (f) Liquid to solid
Multiple Choice Questions
Q-1 Evaporation increases when:

(i)

Humidity is high

(ii)

Temperature is low

(iii)

Liquid is more volatile

(iv)

Surface area is less
Q-2 The container having a volatile liquid is colder because:

(i)

It evaporates faster

(ii)

It expands more on heating

(iii)

It has a higher density

(iv)

They have a high boiling point
Q-3 Boiling temperature of a liquid decreases :

(i)

When small quantity of the liquid is removed

(ii)

At high altitudes

(iii)

When the atmospheric pressure is more

(iv)

When pressure cooker is used
Q-4 If two same sized aluminum rods have different expansion it could be because:

(i)

They are heated at the same temperature

(ii)

They may have different cubical expansion

(iii)

Cannot be explained from the given information

(iv)

They are not heated at the same temperature

Q-5 When a container with a liquid is heated, the liquid level falls in the beginning; this is because :

(i)

The liquid is less volatile than normal

(ii)

Some liquids take time to expand than others

(iii)

In the beginning the container expands on heating

(iv)

It is an error of observation, the experiment should be repeated
Q-6 Steel rod X, is at 10°C and steel rod Y, of the same length is at 30°C; These are both heated to a temperature of 40°C. What kind of linear expansion will they have?

(i)

Rod X, will expand as much as rod Y because they both reach the same temperature.

(ii)

Rod Y will expand less than rod X, because its initial temperature is more.

(iii)

Rod X will expand less than rod Y, because its initial length is less.

(iv)

Expansion of rods X and Y, cannot be calculated with the data give.
Q-7 Which of the following is a wrong statement ?

(i)

Same quantity of a liquids will expand equally for the same rise in temperature.

(ii)

Some liquids expand more than others for the same rise in temperature.

(iii)

Gases expand more than liquids for the same rise in temperature.

(iv)

Thermal expansion in solids is less than gases but more than liquids.

Q-8 Electric cables sag in summer months because of :

(i)

High voltage transmission

(ii)

Low voltage transmission

(iii)

Low resistance of the cables

(iv)

Expansion of the cables

Q-9 Gases expand more on heating because :

(i)

They have high intermolecular attraction.

(ii)

They vibrate about their places on heating.

(iii)

They are less volatile than liquids.

(iv)

They have high intermolecular spaces.

Q-10 Which of the following is the correct statement?

(i)

Gases heated in a closed container show a drop in pressure.

(ii)

In sublimation gases turn to liquid quickly.

(iii)

As ice melts to water its density decreases.

(iv)

When we heat liquids their density usually decreases.

Chapter-7   Sound
Q-1 State True or False and correct the false statements and giving reasons
(1) Longitudinal waves travel by columns of compression and rarefaction.
(2) Loudness of sound depends on nearness of the source of sound.
(3) In longitudinal waves the particle vibrate haphazardly.
(4) A sound of low frequency is always shrill.
(5) The time taken by a vibrating particle is its time period.
(6) A sound of 10 dB, will be painful to the ear.
(7) Monotones have a single frequency.
(8) Sound of 120 dB, can be soft.
(9) Musical notes have irregular vibrations.
(10) In a wind instrument smaller air column produces high pitch sound.
Q-2 Fill in the blanks
(1) A thick string will produce ____________.
(2) Sound cannot travel in ____________.
(3) Number of vibrations per second is a measure of ____________.
(4) High decibel (dB) sound will have ____________.
(5) Shrill sounds have ____________.
(6) The quality of a note is determined by ____________.
(7) To change pitch of a sound the ____________ has to be changed.
(8) Property of ____________ distinguishes sounds with same pitch and loudness.
(9) Unit of loudness is ____________.
(10) In membrane instruments smaller membrane produces ____________ sound.
Q-3 Short answer type questions
(1) Name factor which makes sound louder.
(2) What is a longitudinal wave?
(3) How are time period and frequency related?
(4) How an increase in amplitude affects the loudness of sound?
(5) Two sound waves of the same pitch have their amplitudes in the ratio of 2:3. Calculate the ratio of their loudness.
(6) What is the role of resonance in musical instruments?
(7) When a narrow empty container is put under a water tap how does its sound change as water fills it up?
(8) Give one example of musical instruments which produces notes by : (a) Plucking a string (b) Blowing air (c) Hitting a membrane
(9) What is the use of strings of different thickness in a musical instrument?
(10) What happens to the amplitude when the membrane is large in a musical instrument?
Q-4 Long answer type questions
(1) Explain the propagation of sound in air.
(2) Define amplitude and frequency with the help of a diagram.
(3) Distinguish between music and noise.
(4) How sometimes two similar sounds can produce zero sound?
(5) How are pitch and frequency inter-related, explain?
(6) Explain with a graphic diagram a shrill and loud sound.
(7) How does changes in amplitude, frequency and change of instrument affect the quality of music?
(8) What are the factors that affect the frequencies of a string instrument?
(9) Two sound waves have the same frequency but their amplitude is in the ratio of 1:2. Draw a figure and explain the characteristics of the two sounds.
(10) Loudness and sound intensity are practically the same thing? Explain.
Q-5 Match the features of musical instruments with sound output
Features                                                                  Sound output 1. Thin strings                                                    (a) Lower frequency sound 2. Longer string                                                 (b) High pitch sound  3. Long vibrating column of air                       (c) High frequency sound4. Small tight membrane                                 (d) Grave sound                                                                             (e) No sound is produced
Multiple Choice Questions
Q-1 Which of the following statements is correct about propagation of sound:

(i)

Sound is carried by air particles from source to the ear.

(ii)

Air particles transmit the disturbance in the form of a wave.

(iii)

Louder sounds travel faster than softer sounds

(iv)

Shriller sounds are propagated at a higher speed.
Q-2 If the amplitude of a sound is large it must be :

(i)

Shrill

(ii)

Dull

(iii)

Inaudible

(iv)

Loud

Q-3 In a musical instrument when the length of the string is reduced:

(i)

The pitch become high

(ii)

The pitch become low

(iii)

The loudness increases

(iv)

The loudness is decreased
Q-4 Which of the following is not a string instrument?

(i)

Piano

(ii)

Sitar

(iii)

Harmonium

(iv)

Guitar
Q-5 Which of the following groups has an odd musical instrument?

(i)

Piano, Sitar, Guitar

(ii)

Drum, Tabla, Violin

(iii)

Flute, clarinet, Bugle

(iv)

Sarangi, Banjo, Harp
Q-6 The unit of measuring frequency is :

(i)

Decibel

(ii)

Hertz

(iii)

Amplitude

(iv)

Lambda
Q-7 The frequency of a child’s voice is :

(i)

More than that of an adult male.

(ii)

Same as that of an adult male.

(iii)

Less than that of an adult male.

(iv)

A child's voice has low frequency.
Q-8 A sound of high amplitude and high frequency:

(i)

Will be loud and flat

(ii)

Will be soft and shrill

(iii)

Will be soft and flat

(iv)

Will be loud and shrill

Q-9 A vibration 10 times in one second, will mean;

(i)

A sound of high speed

(ii)

A sound of frequency of 10 Hz.

(iii)

A sound of 10 dB loudness

(iv)

A sound of extremely high pitch
Q-10 While playing the guitar if you want to produce a sound of low pitch:

(i)

String of shorter length will be plucked.

(ii)

The thick string will be plucked.

(iii)

The string will be tightened.

(iv)

The string will be plucked softly.
Chapter-8   Electricity
Q-1 State True or False and correct the false statements giving reasons.
(1) A fuse wire must have high resistance and high melting point.
(2) High star rating of an electrical appliance indicates lower power consumption.
(3) The neutral wire in a live circuit can give a shock.
(4) A thicker fuse wire keeps the appliances safe.
(5) Opposite charges develop when we rub two non-conducting materials.
(6) An atom is neutral because it has neutrons.
(7) When an ebonite rod is rubbed with fur protons move out to the fur.
(8) If there is lightning and thunder it is better to stay indoors.
(9) Lightning is caused by electrical discharge between charged clouds.
(10) The sharp points of the lightning conductor are made of glass.
Q-2 Fill in the blanks
(1) The switch is connected to the ____________ wire.
(2) The thickest pin in a plug is connected to ____________.
(3) The body of an electrical appliance is connected to ____________.
(4) A reason for short circuiting is ____________.
(5) The resistance of the fuse wire should be ____________ than the circuit wires.
(6) Like charges repel but unlike charges ____________.
(7) If an atom had six protons it will also have ____________ electrons.
(8) The gold leaves of a charged electroscope will show ____________.
(9) Gold leaf electroscopes are enclosed in a glass case because ____________.
(10) The lightning conductor should be placed at ____________ of building.
Q-3 Short answer type questions
(1) Name a benefit of the smart meter.
(2) Your MCB, has tripped what action should you take?
(3) Calculate the monthly consumption of electrical energy of an appliance of 150 watt running for eight hours a day in June.
(4) What do you understand by short circuiting?
(5) How is Earthing of an electrical appliance done?
(6) Name the two types of electroscopes?
(7) Why do we say that only repulsion is the sure test of charge on a body?
(8) What are free electrons in a conductor?
(9) Can you give a reason, why dust accumulates on fans so quickly?
(10) Name two safety measures one should take during a thunder shower.
Q-4 Long answer type questions
(1) How does a fuse protect us from a fire hazard?
(2) What are the standard colour coding of electric wires? How does it benefit us?
(3) Name three precautions that we must observe while operating an electrical appliance.
(4) What are the characteristics of an ideal fuse wire?
(5) What is conservation of charge? Explain with an example.
(6) Differentiate between charging by conduction and induction.
(7) How can we check the nature of charge of a charged body using an electroscope?
(8) How does a lightning conductor protect a tall building from lightning?
(9) Why the use of a circuit breaker and Earthing are important in house wiring?
(10) While you can charge a plastic comb by rubbing on your hair, why a metal comb cannot be charged?
Q-5 Match the column
Multiple Choice Questions
Q-1 Conventionally the direction of movement of electrical current in a circuit is pointed as :

(i)

Negative terminal to positive terminal

(ii)

Negative terminal to Earth

(iii)

Earth to positive terminal

(iv)

Positive terminal to negative terminal

Q-2 The difference between a conductor and an insulator is :

(i)

Conductors are made of hard material, insulators are made of soft material.

(ii)

Conductors have free electrons; insulators have very few free electrons.

(iii)

Insulators can be charged by conduction but not conductors.

(iv)

Few conductors are metals but all insulators are non-metals.
Q-3 The meter reading on our electricity bill is written in:

(i)

Volts

(ii)

Amperes

(iii)

Kilowatt-hours

(iv)

Ohms
Q-4 When an electrical switch is put off it disconnects the

(i)

Fuse wire

(ii)

Earth wire

(iii)

Neutral wire

(iv)

Live wire

Q-5 The red or brown coloured wire is always the :

(i)

Earth wire

(ii)

Neutral wire

(iii)

Live wire

(iv)

Fuse wire
Q-6 When we rub an ebonite rod on fur the rod develops negative charge indicating:

(i)

Movement of electron from the rod to the fur.

(ii)

Movement of electrons from the fur to the rod.

(iii)

Movement of protons from the rod to the fur

(iv)

Movement of protons from the fur to the rod.
Q-7 We can generate static electricity by friction on:

(i)

Insulators

(ii)

Conductors

(iii)

Both insulators and conductors

(iv)

Combination of insulators and conductors
Q-8 A metal comb cannot be charged by rubbing on the hair even in dry weather because:

(i)

It is too heavy on the hair

(ii)

It has pointed bristles

(iii)

It will conduct any charge that develops

(iv)

It has no free electrons
Q-9 Which of the following statements is true about charging by induction?

(i)

In induction charging, the charging body should touch very lightly.

(ii)

Opposite charge develops at the far end of the conductor to be charged.

(iii)

Only bodies made of non-conducting material can be charged by induction.

(iv)

Same charge develops at the far end of the conductor to be charged.

Q-10 If the leaves of a negatively charged electroscope collapse upon touching by a rod, the rod must be:

(i)

Uncharged

(ii)

Positively charged

(iii)

Negatively charged

(iv)

Uncharged or positively charged