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: Poisson’s ratio is defined as the ratio of
A) Lateral strain to axial strain
B) Stress to strain
C) Axial strain to lateral strain
D) Shear strain to shear stress
✅ Correct Answer: A
Explanation: Poisson’s ratio is lateral strain divided by axial strain.
Q: Heat is transferred by conduction when
A) Bodies are at same temperature
B) Molecular interaction occurs
C) Radiation dominates
D) There’s motion of fluid
✅ Correct Answer: B
Explanation: Conduction involves transfer through molecular contact.
Q: Unit of thermal conductivity in SI is
A) W/K
B) W/m·K
C) W/m
D) W/m²
✅ Correct Answer: B
Explanation: Thermal conductivity is measured in watts per meter-Kelvin.
Q: In gas turbines, intercooling is used to
A) Reduce work input
B) Increase temperature
C) Increase combustion
D) Increase pressure
✅ Correct Answer: A
Explanation: Intercooling cools compressed air before the next compression stage, reducing work input.
Q: The term “degree of freedom” in mechanics refers to
A) Types of motion
B) Modes of vibration
C) Number of independent motions
D) Number of constraints
✅ Correct Answer: C
Explanation: It refers to the minimum number of independent coordinates needed to define motion.