Mechanical Engineering MCQs
Mechanical Engineering MCQs for competitive exams in Pakistan cover thermodynamics, fluid mechanics, machine design, manufacturing, and materials. Ideal for PPSC, FPSC, NTS, and university tests, they help students and professionals enhance concepts and problem-solving skills.
Q: Entropy increases in a process that is
A) Adiabatic
B) Isothermal
C) Irreversible
D) Reversible
✅ Correct Answer: C
Explanation: In any irreversible process, entropy increases due to energy dispersion.
Q: A perfect gas is characterized by
A) No molecular motion
B) Variable specific heats
C) Compressibility
D) Constant specific heats
✅ Correct Answer: D
Explanation: Ideal gas assumes constant specific heats for simplification.
Q: Governor in engines controls
A) Speed
B) Temperature
C) Compression
D) Fuel mixture
✅ Correct Answer: A
Explanation: A governor maintains a constant engine speed under varying loads.
Q: The highest efficiency of a heat engine is achieved in
A) Carnot cycle
B) Diesel cycle
C) Otto cycle
D) Rankine cycle
✅ Correct Answer: A
Explanation: The Carnot cycle gives the theoretical maximum efficiency.
Q: Flywheel in a machine is used to
A) Transfer heat
B) Absorb shock
C) Store energy
D) Reduce torque
✅ Correct Answer: C
Explanation: Flywheel stores rotational energy to reduce speed fluctuations.