Mechanical Engineering MCQs
Mechanical Engineering MCQs are a crucial resource for students and job seekers preparing for competitive tests in Pakistan. This section features MCQs from all major areas including thermodynamics, fluid mechanics, machine design, manufacturing processes, engineering materials, and mechanics of solids. These questions are crafted to meet the standards of exams like PPSC, FPSC, NTS, and university entry or semester tests. Each MCQ is aimed at testing your fundamental understanding and problem-solving ability, making them perfect for both fresh graduates and experienced professionals. With a wide range of topics, this category ensures a comprehensive practice session for anyone looking to ace Mechanical Engineering exams.
Q: Crankshaft converts
A) Heat to work
B) Rotary to linear motion
C) Linear to rotary motion
D) Work to heat
β
Correct Answer: C
Explanation: The crankshaft transforms the pistonβs linear motion into rotary motion.
Q: Brinell hardness test uses
A) A steel ball
B) A diamond pyramid
C) A flat punch
D) An indenter
β
Correct Answer: A
Explanation: Brinell test uses a hardened steel or tungsten carbide ball to make an indentation.
Q: Shear force in a beam is maximum at
A) Mid-span
B) Neutral axis
C) Free end
D) Fixed end
β
Correct Answer: D
Explanation: In a cantilever or fixed beam, shear is maximum at the support or fixed end.
Q: Tensile test is used to determine
A) Elongation
B) Fracture toughness
C) Modulus of rigidity
D) Impact strength
β
Correct Answer: A
Explanation: A tensile test provides information about ductility and elongation.
Q: In IC engines, knocking occurs due to
A) Early ignition
B) Late ignition
C) Carburetion
D) Detonation
β
Correct Answer: D
Explanation: Knocking is caused by premature combustion of fuel-air mixture, known as detonation.
Q: Entropy increases in a process that is
A) Adiabatic
B) Isothermal
C) Irreversible
D) Reversible
β
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
β
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
β
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
β
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
β
Correct Answer: C
Explanation: Flywheel stores rotational energy to reduce speed fluctuations.