Basic Concepts of Thermodynamics Quiz | Mechanical Principles

Question 1

Which of the following is the SI unit of energy?

Accepted Answer

Joule

Answer

Newton

Answer

Watt

Answer

Kelvin

Question 2

Describe the fundamental difference between heat and work.

Accepted Answer

Heat is energy transfer due to temperature difference, work is energy transfer due to force acting through distance.

Answer

Heat is energy transfer due to force acting through distance, work is energy transfer due to temperature difference.

Answer

Heat and work are equivalent forms of energy.

Answer

Heat is stored energy, while work is transferred energy.

Question 3

Define an isothermal process in thermodynamics.

Accepted Answer

Temperature remains constant throughout the process.

Answer

Pressure remains constant throughout the process.

Answer

Volume remains constant throughout the process.

Answer

Entropy remains constant throughout the process.

Question 4

Explain what an adiabatic process entails.

Accepted Answer

No heat transfer occurs between the system and its surroundings.

Answer

Temperature remains constant throughout the process.

Answer

Pressure remains constant throughout the process.

Answer

Volume remains constant throughout the process.

Question 5

Define the efficiency of a heat engine.

Accepted Answer

Ratio of work output to heat input

Answer

Ratio of heat input to work output

Answer

Ratio of internal energy change to heat input

Answer

Ratio of internal energy change to work output

Question 6

What is the Carnot cycle in thermodynamics?

Accepted Answer

A theoretical heat engine cycle with maximum possible efficiency.

Answer

A practical heat engine cycle commonly used in applications.

Answer

A cycle describing refrigerator operation.

Answer

A cycle describing heat pump operation.

Question 7

Define entropy in thermodynamics.

Accepted Answer

A measure of system disorder

Answer

A measure of system energy

Answer

A measure of system temperature

Answer

A measure of system pressure

Question 8

Which of the following is the energy transferred between objects at different temperatures?

Accepted Answer

Heat

Answer

Work

Answer

Potential energy

Answer

Chemical energy

Question 9

According to the first law of thermodynamics, the total amount of energy in an isolated system:

Accepted Answer

Remains constant

Answer

Increases

Answer

Decreases

Answer

Fluctuates

Question 10

In a closed system, which of the following is not conserved?

Accepted Answer

Volume

Answer

Mass

Answer

Energy

Answer

Momentum

Question 11

The mathematical expression for the first law of thermodynamics is:

Accepted Answer

dE = Q - W

Answer

dE = Q + W

Answer

Q = dE + W

Answer

W = Q + dE

Question 12

Which of the following processes involves no change in temperature?

Accepted Answer

Expansion of a gas at constant temperature

Answer

Melting of ice

Answer

Adiabatic compression

Answer

Evaporation of water

Question 13

The internal energy of an ideal gas depends primarily on:

Accepted Answer

Temperature

Answer

Volume

Answer

Pressure

Answer

Number of molecules

Question 14

Which of the following statements about entropy is true?

Accepted Answer

Entropy always increases in any spontaneous process.

Answer

Entropy remains constant in any spontaneous process.

Answer

Entropy always decreases in any spontaneous process.

Answer

Entropy can increase or decrease in any spontaneous process.

Question 15

Which of the following materials is the best conductor of heat?

Accepted Answer

Copper

Answer

Wood

Answer

Plastic

Answer

Rubber

Question 16

Which of the following is NOT considered a fundamental form of energy?

Accepted Answer

Mass

Answer

Heat

Answer

Work

Answer

Electricity

Question 17

According to the first law of thermodynamics, what happens to energy within a closed system?

Accepted Answer

Energy can be transferred or transformed, but not created or destroyed.

Answer

Energy can be created or destroyed.

Answer

Heat and work are always equal.

Answer

Entropy always increases.

Question 18

Which of the following is an example of a closed system in thermodynamics?

Accepted Answer

A sealed container filled with gas

Answer

A car engine operating with an open intake and exhaust system

Answer

A cup of hot coffee exposed to the surrounding air

Answer

The Earth's atmosphere interacting with its surroundings

Question 19

What is the standard international unit of energy used in the SI system?

Accepted Answer

Joule

Answer

Kelvin

Answer

Watt

Answer

Calorie

Question 20

Which of the following concepts is associated with the level of disorder or randomness within a system?

Accepted Answer

Entropy

Answer

Enthalpy

Answer

Exergy

Answer

Efficiency

Question 21

What is the fundamental relationship between heat and work in thermodynamics?

Accepted Answer

Heat and work can be converted into each other, but are not always equal.

Answer

Heat and work are always equal and cannot be converted into each other.

Answer

Heat and work are independent of each other and cannot be interchanged.

Answer

Heat is a form of work, but work is not a form of heat.

Question 22

Which of the following reactions is classified as exothermic?

Accepted Answer

Combustion of fuel, releasing heat and light

Answer

Melting of ice, absorbing heat from the surroundings

Answer

Evaporation of water, requiring heat to transform from a liquid to a gas

Answer

Photosynthesis, converting light energy into chemical energy

Question 23

In an isothermal process, what happens to the entropy of the system?

Accepted Answer

Entropy remains constant.

Answer

Entropy increases.

Answer

Entropy decreases.

Answer

Entropy becomes zero.