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The following are the  Multiple Choice Questions (MCQs) related to the topic Heat Transfer from Physics along with answers. This will be helpful for Engineering degree, diploma and post graduate engineering students.

1 The capacity to do work is called as:

A. Heat
B. Energy
C. work
D. none of the above

Ans: B

2 Heat is measured in:

A. Joule
B. Calorie
C. both A and B
D. Joule/second

Ans: A   It is measured in Joule .

3 1 cal. = ?

A. 1.2 joule
B. 3.2 joule
C. 4.2 joule
D. none of the above

Ans: C

4 The form of energy that produces feeling of hotness is called as:

A. work
B. Heat
C. Energy
D. none of the above

Ans: B

5 With increase in temperature, heat will be:

A. increase
B. constant
C. dcrease
D. double

Ans: A    Heat increase in temperature

6 How we measure energy value of food?

A. Joule
B. Joule/second
C. Calorie
D. none of the above

Ans: C    Calorie is used to measure energy value of food. 1 cal. =4.2 joule

7 The amount of heat required to raise temperature of a substance by 1°C is called as:

A. work capacity
B. heat capacity
C. Energy capacity
D. none of the above

Ans: B

8 Heat capacity depends on

A. change in temperature
B. Mass of body
C. Nature of substance
D. All the above

Ans: D   It depends on (a) Mass of body (b) change in temperature (c) Nature of substance.

9 Heat bring ……………… change

A. Physical
B. chemical
C. reversible
D. periodic

Ans: B   Heat bring chemical change

10 ………………….. is neither created nor destroyed it can only changed one form to another.

A. work
B. Heat
C. Energy
D. Mass of body

Ans: C  Energy is neither created nor destroyed it can only changed one form to another.

11 The amount of heat required to raise temperature of a substance by …………..

A. 1°C
B. 1°F
C. 10°C
D. 10°F

Ans: A

12 The amount of heat required to raise the temperature of 1 kg by 1°C is called as:

A. heat capacity
B. work capacity
C. specific heat capacity
D. Energy capacity

Ans: C

13 SI unit of specific heat capacity is:

A. kg°C
B. j/kg°C
C. j/kg°
D. j/g°C

Ans: B

14 Which of the following has highest heat capacity?

A. Water
B. air
C. soil
D. none of the above

Ans: A   Water has highest heat capacity.

15 Which of the following are the processes of transfer of heat?

A. Conduction
B. Convection
D. All the above

Ans: D  Conduction, Convection & Radiation are three processes of transfer of heat.

16 The process of transfer of heat in solids is called as:

A. Convection
C. Conduction
D. none of the above

Ans: C  In this process the molecules of the solid pass the heat from one to another, without themselves moving from their positions.

17 The temperature at which liquid changes into vapour is called as:

A. Melting point
B. boiling point.
C. expansion point
D. none of the above

Ans: B

18 In Conduction process the molecules of the solid pass the heat from one to another,:

A. without themselves moving from their positions.
B. themselves move from one place to another
C. without themselves moving from one place to another.
D. None of the above

Ans: A In this process the molecules of the solid pass the heat from one to another, without themselves moving from their positions.

19 The process of transfer of heat in liquids & gases is called as:

A. Conduction
C. Convection
D. absorption

Ans: C  It is the process of transfer of heat in liquids & gases

20 In convection, the molecules:

A. without themselves moving from their positions.
B. themselves move from one place to another
C. without themselves moving from one place to another.
D. None of the above

Ans: B  In convection, the molecules themselves move from one place to another, carrying heat with them.

21 Solids are not heated by convection because:

A. solid are not free to move from one place to another
B. molecules only vibrate about fixed position
C. both A and B
D. none of the above

Ans: C  Solids are not heated by convection because the molecules of a solid are not free to move from one place to another; they can only vibrate about fixed position

22 It is the process of heat transfer from a hot body to a colder body without heating the space between the two is called as:

A. Conduction
C. Convection
D. absorption

Ans: B

23 At night a current of air blows from the colder land to the warmer sea is called as:

A. air Breezes
B. Sea Breezes
C. Land Breeze
D. none of the above

Ans: C  the sea is warmer than the land at night. So at night a current of air blows from the colder land to the warmer sea. This is called the land breeze.

24 The transfer of heat by radiation :

A. does not require any medium.
B. require any medium.
C. does not require any space.
D. require any space.

Ans: A The transfer of heat by radiation does not require any medium.

25 Air over the land is heated, becomes lighter & rises while the cooler air from the sea blows towards land to take its place is called as:

A. Land Breeze
B. Sea Breezes
C. air Breezes
D. none of the above

Ans: B  During the day, the land is heated by sun to a higher temperature than the water in the sea. Air over the land is heated, becomes lighter & rises while the cooler air from the sea blows towards land to take its place.

26 At what factor heat absorbed on radiation by body depends on?

A. Distance between body
B. source of heat
C. its colour
D. All the above

Ans: D (Black coloured surface absorb more than white surfaces)

27 Heat of sun reach the earth by :

B. Convection
C. absorption
D. Conduction

Ans: A

28 Land breeze blows during :

A. à day
B. à night
C. à winter
D. à summer

Ans: B

29 A wooden spoon is dipped in a cup of ice cream. Its other end..

A. becomes cold by the process of radiation.
B. becomes cold by the process of conduction.
C. “does not become cold.”
D. becomes cold by the process of convection.

Ans: C

30 Sea breeze blows during:

A. à summer
B. à winter
C. à day
D. à night

Ans: C

31 A cold steel spoon is dipped in a cup of hot milk. It transfers heat to its other end by the process of…………….

A. Convection
B. Conduction
C. absorption

Ans: B

32 Clothes of ………………… colours absorb heat better than clothes of ………….colours.

A. Light, dark
B. dark, light
C. soft, dark,
D. none of the above

Ans: B

33 Dark coloured clothes are preferred during:

A. à winter
B. à day
C. à night
D. à summer

Ans: A

34 No medium is required for transfer of heat by the process of :

A. absorption
B. Conduction
D. Convection

Ans: C

35 Light coloured clothes are preferred during

A. à winter
B. à summer
C. à day
D. à night

Ans: B

36 Why conduction is only possible in solids:

A. particles of solids are closely packed
B. heat is transferred from the hotter end to the colder end of an object.
C. heat is transferred from the colder end to the hotter end of an object.
D. both A and B

Ans: D In solids, generally, the heat is transferred by the process of conduction because particles of solids are closely packed and heat is transferred from the hotter end to the colder end of an object.

37 The water is poor conductors of heat so do not heated by:

A. absorption
B. Conduction
D. Convection

Ans: B  The cold water from the sides moves down towards the source of heat This water also gets hot and rises and water from the sides moves down. This process continues till the whole water gets heated. This mode of heat transfer is known as convection

38 An iron ball at 40°C is dropped in a mug containing water at 40°C. The heat will….

A. not flow from iron ball to water or from water to iron ball.
B. flow from iron ball to water.
C. flow from water to iron ball.
D. none of the above

Ans: A

39 The materials which allow heat to pass through them easily are called as:

A. insulators of heat
B. conductors of heat
C. semi conductors of heat
D. none of the above

Ans: B

40 Stainless steel pans are usually provided with copper bottoms. The reason for this could be that.

A. copper bottom makes the pan more durable.
B. such pans appear colorful.
C. copper is a better conductor of heat than the stainless steel.
D. none of the above

Ans: C

41 Which of the following are the examples of conductors?

A. plastic
B. iron
C. wood
D. silicon

Ans: B  “For examples, aluminum, iron and copper. ”

42 The materials which do not allow heat to pass through them easily are called as:

A. conductors of heat
B. semi conductors of heat
C. insulators of heat
D. none of the above

Ans: C “Poor conductors are known as insulators”

43 Which of the following are the examples of insulators ?

A. wood
B. silicon
C. copper
D. Alluminium

Ans: A “poor conductors of heat such as plastic and wood.”

44 Radiation is the transfer of heat by means of:

A. magnetic wave
B. electromagnetic waves.
C. electrical wave
D. none of the above

Ans: B

45 The effect of a material upon heat transfer rates is often expressed in terms of a number known as :

A. Electrical conductivity
B. conductivity
C. thermal conductivity
D. none of the above

Ans: C The effect of a material upon heat transfer rates is often expressed in terms of a number known as the thermal conductivity.

46 Thermal conductivity values are…………………… that are determined by experiment.

A. alphanumerical values
B. numerical values
C. roman values
D. All the above

Ans: B

47 What is the thermal conductivity values for Water ?

A. 0.13
B. 2.18
C. 0.58
D. 0.06

Ans: C

48 The equation relating the heat transfer rate glass window consists of:

A. surface area
B. thickness
C. thermal conductivity value
D. All the above

Ans: D

49 The units on the rate of heat transfer are:

A. Calorie/second
B. Joule
C. Joule/second
D. Calorie

Ans: C The units on the rate of heat transfer are Joule/second, also known as a Watt.

50 What does ‘A’ represent in the equation relating the heat transfer rate ?

A. ampere
B. area
C. thickness
D. none of the above

Ans: B The window has a surface area A

51 What is the thermal conductivity values for Copper ?

A. 398
B. 315
C. 237
D. 110

Ans: A

52 What does ‘k’ represent in the equation relating the heat transfer rate ?

A. thickness

B. temperature
C. thermal conductivity
D. none of the above

Ans: C The thermal conductivity value of the window glass is k.

53 The Joule/second is also known as:

A. Watt
B. Coloumb
C. Newton
D. none of the above

Ans: A The units on the rate of heat transfer are Joule/second, also known as a Watt.

54 What does ‘d’ represent in the equation relating the heat transfer rate ?

A. area
B. thickness
C. temperature
D. distance

Ans: B

55 What is the thermal conductivity values for Brass ?

A. 110
B. 398
C. 315
D. 237

Ans: A

56 If the area through which heat is transferred is increased by a factor of 2, then the rate of heat transfer is ……………….. .

A. increased by a factor of 2
B. decreased by a factor of 2
C. increased by a factor of 4
D. decreased by a factor of 4

Ans: A

57 If the thermal conductivity of the material through which heat is transferred is increased by a factor of 5, then the rate of heat transfer is…………………..

A. decreased by a factor of 2
B. increased by a factor of 4
C. increased by a factor of 5
D. decreased by a factor of 5

Ans: C

58 What is the thermal conductivity values for alluminium ?

A. 200
B. 237
C. 230
D. 227

Ans: B

59 If the thickness of the material through which heat is transferred is increased by a factor of 2, then the rate of heat transfer is……………………

A. increased by a factor of 4
B. decreased by a factor of 4
C. increased by a factor of 2
D. decreased by a factor of 2

Ans: D

60 The equation relating the heat transfer rate to these variables is:

A. Rate = k•(T1 – T2)/d
B. Rate = k•A•(T1 – T2)/d
C. Rate = A•(T1 – T2)/d
D. Rate = k•A•(T1 – T2)/r

Ans: B the transfer of heat through a glass window from the inside of a home with a temperature of T1 to the outside of a home with a temperature of T2. The window has a surface area A and a thickness d.

61 Thermal radiation travels through vacuum on ………………..line

A. straight
B. zigzag
C. vertical
D. diagonal

Ans: A Thermal radiation travels through vacuum on straight line and with the velocity of light.

62 Thermal radiations can be ………… and ……………..

A. reflected and absorbed
B. refracted and absorbed
C. reflected and refracted
D. none of the above

Ans: C Thermal radiations can be reflected and refracted

63 Kelvin scale is also called as:

A. Celsius scale
B. absolute scale
C. Fahrenheit scale
D. All the above

Ans: B Kelvin scale is also called absolute scale of temperature.

64 The interval between the lower and upper fixed points is divided in a suitable number of equal parts depending upon the scales of temperature is called as:

A. parts
B. section
C. degree
D. none of the above
Ans: C  Each interval is called a degree

65 Kelvin scale, the interval is divided in :

A. 100 equal parts
B. 180 equal parts
C. both A and B
D. none of the above
Ans: A  For Celsius (or centigrade ) scale and Kelvin scale, the interval is divided in 100 equal parts

66 The effects of heat on an object are :

A. never change in shape of a body
B. Change in temperature of a body
C. never change state of matter
D. All the above

Ans: B  Change in temperature of a body