Master Thermodynamics: Laws and Applications in Engineering Systems

Question 1

Which statement is NOT part of the first law of thermodynamics?

Accepted Answer

The total entropy of an isolated system can only increase.

Answer

Energy cannot be created or destroyed.

Answer

Heat is a form of energy.

Answer

Work can be converted into heat.

Question 2

In an adiabatic process, which of the following occurs?

Accepted Answer

There is no heat transfer between the system and its surroundings.

Answer

Heat is added to or removed from the system.

Answer

The temperature of the system remains constant.

Answer

The work done by the system is equal to the heat added to the system.

Question 3

What unit of measurement is used for entropy?

Accepted Answer

Joules per kelvin.

Answer

Watts per meter.

Answer

Newtons per square meter.

Answer

Pascals per second.

Question 4

According to the First Law of Thermodynamics, the total energy of an isolated system is:

Accepted Answer

Constant

Answer

Decreasing

Answer

Increasing

Answer

Zero

Question 5

A heat engine is a device that converts:

Accepted Answer

Heat into mechanical energy

Answer

Heat into electrical energy

Answer

Mechanical energy into heat

Answer

Electrical energy into heat

Question 6

The entropy of a system is a measure of its:

Accepted Answer

Disorder

Answer

Order

Answer

Energy

Answer

Temperature

Question 7

The efficiency of a heat pump is measured by its:

Accepted Answer

Coefficient of performance

Answer

Carnot efficiency

Answer

Thermal efficiency

Answer

Power factor

Question 8

Which of the following is a greenhouse gas?

Accepted Answer

Carbon dioxide

Answer

Nitrogen

Answer

Oxygen

Answer

Hydrogen

Question 9

The global warming potential of a gas is a measure of its:

Accepted Answer

Impact on climate change

Answer

Ability to absorb heat

Answer

Toxicity

Answer

Flammability

Question 10

Which of the following is NOT a thermodynamic property?

Accepted Answer

Gravitational potential energy

Answer

Internal energy

Answer

Entropy

Answer

Volume

Question 11

The first law of thermodynamics is based on the principle of:

Accepted Answer

Conservation of energy

Answer

Conservation of mass

Answer

Conservation of momentum

Answer

Reversibility

Question 12

The enthalpy of a system is defined as:

Accepted Answer

Internal energy + PV

Answer

Internal energy - PV

Answer

PV + RT

Answer

PV - RT

Question 13

Which of the following statements accurately describes the difference between a closed and an open thermodynamic system?

Accepted Answer

A closed system prevents matter from crossing its boundaries, while an open system allows it.

Answer

A closed system allows matter to pass through its boundaries, while an open system does not.

Answer

Both closed and open systems allow matter to pass through their boundaries.

Answer

Neither closed nor open systems allow matter to pass through their boundaries.

Question 14

During an isobaric expansion of an ideal gas, which of the following is true about the work done?

Accepted Answer

Work is done by the gas.

Answer

No work is done.

Answer

Work is done on the gas.

Answer

Heat is absorbed by the gas.

Question 15

For a cyclic process, which of the following statements about net work and heat transfer is correct?

Accepted Answer

Net work done = Net heat transferred to the system.

Answer

Net work done < Net heat transferred to the system.

Answer

Net work done > Net heat transferred to the system.

Question 16

Which of the following processes is inherently irreversible?

Accepted Answer

Heat transfer through a temperature gradient

Answer

Isothermal expansion

Answer

Adiabatic compression

Answer

Reversible heat engine cycle

Question 17

During an adiabatic process, the system's entropy change is:

Accepted Answer

Zero.

Answer

Negative.

Answer

Undefined.

Answer

Positive.

Question 18

How does a heat pump differ from a refrigerator in terms of its thermodynamic function?

Accepted Answer

A heat pump transfers heat from a cold reservoir to a hot reservoir, while a refrigerator transfers heat from a hot reservoir to a cold reservoir.

Answer

A heat pump has a higher COP than a refrigerator.

Question 19

In an isothermal process of an ideal gas, which property remains constant?

Accepted Answer

Temperature

Answer

Volume

Answer

Entropy

Answer

Pressure

Question 20

Which of the following is NOT a type of thermodynamic system?

Accepted Answer

Semi-closed system

Answer

Isolated system

Answer

Open system

Answer

Closed system

Question 21

A system undergoes a process where its internal energy decreases by 100 J and work is done on the system by an external force of 50 J. What is the net heat transfer to the system?

Accepted Answer

-150 J

Answer

+150 J

Answer

-50 J

Answer

+50 J

Question 22

According to the Second Law of Thermodynamics, which of the following statements is true?

Accepted Answer

The total entropy of an isolated system always increases over time.

Answer

The entropy of an isolated system remains constant over time.

Answer

The total entropy of an isolated system decreases over time.

Answer

The entropy of an open system always decreases over time.

Question 23

Which of the following is the maximum theoretical efficiency of a heat engine operating between two reservoirs at different temperatures?

Accepted Answer

Carnot efficiency

Answer

Diesel efficiency

Answer

Otto efficiency

Answer

Rankine efficiency

Question 24

In a refrigeration cycle, at what temperature does the refrigerant absorb heat from the cold reservoir?

Accepted Answer

Below its boiling point

Answer

At room temperature

Answer

Above its boiling point

Answer

At its boiling point

Question 25

What is the change in enthalpy of a closed system equal to?

Accepted Answer

Heat transfer at constant pressure

Answer

Internal energy change

Answer

Work done on the system

Answer

Heat transfer at constant volume

Question 26

The Third Law of Thermodynamics states that:

Accepted Answer

The entropy of a perfect crystal approaches zero as the temperature approaches absolute zero

Answer

Heat cannot flow spontaneously from a colder to a hotter object

Answer

The entropy of a system always increases