Thermodynamics MCQ Set 2
THERMODYNAMICS MCQ SET 1
Q1. In a reversible process, entropy:
A) Increases
B) Decreases
C) Remains constant
D) Becomes zero
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Answer: C) Remains constant
Explanation: For reversible processes, there is no entropy generation.
Q2. Specific heat at constant pressure is always:
A) Less than Cp
B) Greater than Cv
C) Equal to Cv
D) Zero
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Answer: B) Greater than Cv
Explanation: At constant pressure, part of the heat is used to do work, so Cp > Cv.
Q3. The ratio of Cp/Cv is called:
A) Entropy
B) Specific heat ratio (γ)
C) Thermal efficiency
D) Temperature ratio
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Answer: B) Specific heat ratio (γ)
Explanation: The ratio of specific heats is denoted by γ = Cp/Cv.
Q4. Work done in an isochoric process is:
A) Maximum
B) Minimum
C) Zero
D) Constant
Show AnswerAnswer: C) Zero
Explanation: In a constant volume process, no boundary work is done.
Q5. The internal energy of an ideal gas depends only on:
A) Volume
B) Pressure
C) Temperature
D) Density
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Answer: C) Temperature
Explanation: Internal energy for an ideal gas is a function of temperature only.
Q6. One kilocalorie equals:
A) 4.184 kJ
B) 418.4 kJ
C) 41.84 J
D) 0.4184 kJ
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Answer: A) 4.184 kJ
Explanation: 1 kcal = 4.184 kilojoules.
Q7. The work done in a reversible adiabatic process is:
A) Maximum
B) Minimum
C) Zero
D) Negative
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Answer: A) Maximum
Explanation: For a given change, adiabatic reversible process gives maximum work.
Q8. Which law of thermodynamics introduces the concept of entropy?
A) Zeroth law
B) First law
C) Second law
D) Third law
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Answer: C) Second law
Explanation: The second law introduces entropy and direction of energy flow.
Q9. The efficiency of a Carnot engine is:
A) 1 – (T2/T1)
B) 1 + (T2/T1)
C) (T2/T1)
D) (T1/T2)
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Answer: A) 1 – (T2/T1)
Explanation: Carnot efficiency depends on temperature ratio between sink (T2) and source (T1).
Q10. The Kelvin-Planck statement is related to:
A) First law
B) Second law
C) Third law
D) Zeroth law
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Answer: B) Second law
Explanation: It states that no device can convert all heat into work in a cyclic process.