Thermodynamics MCQ Set 1

THERMODYNAMICS MCQ SET 1

Q1. Which of the following is a thermodynamic property?

A) Pressure
B) Volume
C) Temperature
D) All of the above

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Answer: D) All of the above
Explanation: Pressure, volume, and temperature are all measurable properties that define a thermodynamic system.

Q2. The first law of thermodynamics is based on the law of:

A) Conservation of momentum
B) Conservation of energy
C) Conservation of mass
D) Conservation of entropy

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Answer: B) Conservation of energy
Explanation: Energy can neither be created nor destroyed; it only changes its form.

Q3. In an adiabatic process, there is no:

A) Work transfer
B) Heat transfer
C) Change in pressure
D) Change in temperature

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Answer: B) Heat transfer
Explanation: Adiabatic process means no heat is exchanged with surroundings.

Q4. A process in which pressure remains constant is called:

A) Isochoric
B) Isobaric
C) Isothermal
D) Adiabatic

Show AnswerAnswer: B) Isobaric
Explanation: “Isobaric” means constant pressure throughout the process.

Q5. The unit of entropy is:

A) kJ/kg
B) kJ/kg·K
C) J/kg
D) kcal/kg

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Answer: B) J/kg·K
Explanation:
Entropy measures energy dispersal per unit temperature per unit mass.

Q6. The Zeroth law of thermodynamics defines:

A) Energy conservation
B) Temperature
C) Entropy
D) Work done

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Answer: B) Temperature
Explanation: It states that if two bodies are each in thermal equilibrium with a third body, they are in thermal equilibrium with each other.

Q7. The process with constant volume is known as:

A) Isochoric
B) Isothermal
C) Isobaric
D) Adiabatic

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Answer: A) Isochoric
Explanation: In an isochoric process, volume remains constant, so no work is done.

Q8. Which cycle is used in a steam power plant?

A) Otto cycle
B) Diesel cycle
C) Rankine cycle
D) Brayton cycle

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Answer: C) Rankine cycle
Explanation: Rankine cycle is used in thermal power plants to convert heat into work.

Q9. The device that converts heat energy into mechanical work is called:

A) Compressor
B) Turbine
C) Heat engine
D) Pump

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Answer: C) Heat engine
Explanation: A heat engine converts heat energy into mechanical energy.

Q10. The efficiency of a Carnot engine depends on:

A) Working fluid
B) Temperatures of source and sink
C) Pressure ratio
D) Type of fuel

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Answer: B) Temperatures of source and sink
Explanation: Efficiency increases when the temperature difference between source and sink increases.