Thermal Energy: Heat, Specific Heat, Latent Heat, Thermal Expansion

Question 1

The specific heat of a substance is defined as the amount of heat required to raise the temperature of one gram of the substance by one degree Celsius.

Accepted Answer

True

Answer

False

Question 2

Which of the following materials has the highest specific heat?

Accepted Answer

Water

Answer

Aluminum

Answer

Iron

Answer

Air

Question 3

Latent heat is the heat that is absorbed or released when a substance changes phase.

Accepted Answer

True

Answer

False

Question 4

Thermal expansion can cause stresses in materials.

Accepted Answer

True

Answer

False

Question 5

Thermal expansion is an important consideration in the design of bridges.

Accepted Answer

True

Answer

False

Question 6

Which of the following is the SI unit of thermal energy?

Accepted Answer

Joule

Answer

Kelvin

Answer

Watt

Answer

Celsius

Question 7

The specific heat capacity of a substance is defined as:

Accepted Answer

The amount of heat required to raise the temperature of 1 kg of the substance by 1 degree Celsius

Answer

The ratio of the amount of heat absorbed by a substance to its mass

Answer

The amount of heat required to melt 1 kg of the substance

Answer

The change in temperature of a substance when it absorbs 1 J of heat

Question 8

Which of the following materials has the highest specific heat capacity?

Accepted Answer

Water

Answer

Air

Answer

Iron

Answer

Wood

Question 9

Latent heat is the heat associated with:

Accepted Answer

A change of phase

Answer

A change in temperature

Answer

A chemical reaction

Answer

A nuclear reaction

Question 10

Thermal expansion is the increase in volume of a substance due to:

Accepted Answer

Temperature change

Answer

Pressure change

Answer

Chemical change

Answer

Electrical change

Question 11

A heat engine converts:

Accepted Answer

Heat into mechanical energy

Answer

Mechanical energy into heat

Answer

Electrical energy into heat

Answer

Chemical energy into heat

Question 12

The efficiency of a heat engine is defined as:

Accepted Answer

The ratio of the work output to the heat input

Answer

The ratio of the heat input to the work output

Answer

The change in temperature of the working fluid

Answer

The specific heat capacity of the working fluid

Question 13

What is the main purpose of a heat sink?

Accepted Answer

To transfer heat away from a component

Answer

To generate heat

Answer

To store heat

Answer

To insulate a component

Question 14

Which of the following units represents heat capacity?

Accepted Answer

Joule per kilogram-Kelvin

Answer

Joule per kilogram

Answer

Joule per second

Answer

Watt per kilogram-Kelvin

Question 15

Identify the process by which a substance transitions from a liquid to a gaseous state?

Accepted Answer

Evaporation

Answer

Condensation

Answer

Freezing

Answer

Sublimation

Question 16

Identify the equation that relates heat transfer to mass, specific heat, and temperature change:

Accepted Answer

Q = mcΔT

Answer

Q = cΔTm

Answer

Q = mΔTc

Answer

Q = cΔTt

Question 17

Select the SI unit of thermal conductivity:

Accepted Answer

Watts per meter-Kelvin

Answer

Joules per meter-second-Kelvin

Answer

Watts per kilogram-Kelvin

Answer

Joules per kilogram-second-Kelvin

Question 18

Identify a material with good insulating properties:

Accepted Answer

Air

Answer

Water

Answer

Copper

Answer

Steel

Question 19

Select the process by which heat is transferred through fluid movement:

Accepted Answer

Convection

Answer

Conduction

Answer

Radiation

Answer

Evaporation

Question 20

Which option is NOT a valid mode of heat transfer?

Accepted Answer

Magnetic transfer

Answer

Radiation

Answer

Conduction

Answer

Convection

Question 21

Select the primary heat transfer mechanism in a vacuum:

Accepted Answer

Radiation

Answer

Conduction

Answer

Convection

Answer

Evaporation

Question 22

How do modern bridge designs address thermal expansion?

Accepted Answer

Compensate for temperature changes to prevent damage from expansion and contraction

Answer

Reduce bridge weight by using lightweight materials that expand easily

Answer

Increase bridge flexibility to withstand wind and seismic forces

Answer

Enhance the bridge's aesthetic appeal with unique architectural features

Question 23

What is the SI unit of heat?

Accepted Answer

Joule

Answer

Calorie

Answer

British Thermal Unit

Answer

Kilowatt-hour

Question 24

Define the specific heat of a substance.

Accepted Answer

The amount of heat energy needed to increase the temperature of one gram of the substance by one degree Celsius.

Answer

The amount of heat released when one gram of the substance cools down by one degree Celsius.

Answer

The ratio of heat capacity to mass.

Answer

The heat required to change the phase of one gram of the substance.

Question 25

Which of the following is not a method of heat transfer?

Accepted Answer

Evaporation

Answer

Conduction

Answer

Convection

Answer

Radiation

Question 26

Define the latent heat of fusion.

Accepted Answer

The heat needed to melt a solid into a liquid.

Answer

The heat needed to boil a liquid into a gas.

Answer

The heat released when a gas condenses to a liquid.

Answer

The heat released when a liquid freezes to a solid.

Question 27

What is the coefficient of thermal expansion?

Accepted Answer

The change in length per unit change in temperature.

Answer

The change in volume per unit change in temperature.

Answer

The change in pressure per unit change in temperature.

Answer

The change in specific heat per unit change in temperature.

Question 28

What is the function of a heat engine?

Accepted Answer

To convert heat into work.

Answer

To convert work into heat.

Answer

To store heat.

Answer

To transfer heat.

Question 29

What is the significance of the Carnot cycle?

Accepted Answer

It is a theoretical heat engine cycle with the highest possible efficiency.

Answer

It is a real heat engine cycle with the same efficiency as the Carnot cycle.

Answer

It is a heat engine cycle used in most practical applications.

Answer

It is a heat engine cycle that is impossible to build.

Question 30

What is the International System of Units (SI) unit of heat energy?

Accepted Answer

Joule

Answer

Calorie

Answer

British Thermal Unit

Answer

Kiloelectronvolt

Question 31

The specific heat of a substance is defined as the amount of heat energy required to raise the temperature of one kilogram of the substance by one degree Celsius.

Accepted Answer

True

Answer

False

Question 32

Which of the following substances has the highest specific heat capacity?

Accepted Answer

Water

Answer

Ice

Answer

Aluminum

Answer

Copper

Question 33

Which of the following is NOT a type of thermal expansion?

Accepted Answer

Surface area expansion

Answer

Linear expansion

Answer

Volume expansion

Answer

Isotropic expansion

Question 34

The coefficient of linear expansion is a measure of the fractional change in length of a material per unit change in temperature.

Accepted Answer

True

Answer

False

Question 35

Which of the following materials has the highest coefficient of linear expansion?

Accepted Answer

Aluminum

Answer

Steel

Answer

Copper

Answer

Glass

Question 36

Thermal stresses can occur in materials when they are subjected to non-uniform temperature distributions.

Accepted Answer

True

Answer

False

Question 37

Which of the following is the SI unit of thermal energy?

Accepted Answer

Joule

Answer

Calorie

Answer

Watt

Answer

Kelvin

Question 38

A substance with a high specific heat capacity requires

Accepted Answer

More energy to raise its temperature by the same amount

Answer

Less energy to raise its temperature by the same amount

Answer

More time to raise its temperature by the same amount

Answer

Less time to raise its temperature by the same amount

Question 39

A metal rod is heated at one end. Which of the following statements is true about the thermal expansion of the rod?

Accepted Answer

The rod expands more at the heated end

Answer

The rod expands uniformly throughout its length

Answer

The rod contracts at the heated end

Answer

The rod does not expand or contract

Question 40

Which of the following is the primary mode of heat transfer in a vacuum?

Accepted Answer

Radiation

Answer

Conduction

Answer

Convection

Answer

Evaporation

Question 41

A heat exchanger is used to transfer heat between two fluids. Which of the following factors does NOT affect the rate of heat transfer?

Accepted Answer

Fluid viscosity

Answer

Surface area of the exchanger

Answer

Temperature difference between the fluids

Answer

Fluid flow rate

Question 42

The efficiency of a heat engine is defined as the ratio of

Accepted Answer

Work output to heat input

Answer

Heat input to work output

Answer

Heat rejected to heat input

Answer

Work output to heat rejected

Question 43

Which of the following is a thermodynamic system that is completely isolated from its surroundings?

Accepted Answer

A closed thermos bottle

Answer

A cup of hot coffee

Answer

A refrigerator

Answer

A heated swimming pool

Question 44

The first law of thermodynamics states that

Accepted Answer

Energy cannot be created or destroyed

Answer

Entropy increases in all spontaneous processes

Answer

Heat flows from hot to cold

Answer

The volume of a gas is inversely proportional to its temperature