MCQ Questions and Answers Flashcards

A cam mechanism converts which type of motion?

Answer: Rotary to reciprocating or oscillating

A cam converts rotary motion into reciprocating (back-and-forth) or oscillating motion. As the cam rotates, its shaped profile pushes a follower in a predetermined pattern, used extensively in engine valve trains.

What is the SI unit of torque?

Answer: Newton-meter

Torque is measured in Newton-meters (N·m) in the SI system. While dimensionally equivalent to joules (also N·m), torque uses Newton-meters by convention to distinguish it from energy.

Which of these is NOT one of the six classical simple machines?

Answer: Spring

The six classical simple machines are: lever, wheel and axle, pulley, inclined plane, wedge, and screw. A spring is an elastic device that stores and releases energy but is not classified as a simple machine.

What does the coefficient of friction depend on?

Answer: The materials and condition of the two surfaces in contact

The coefficient of friction depends on the nature of the two surfaces in contact — their materials, roughness, temperature, and whether they are dry or lubricated. It does not depend on the apparent contact area or the normal force.

Heat always flows naturally from:

Answer: Hot objects to cold objects

The Second Law of Thermodynamics dictates that heat spontaneously flows from hotter objects to cooler objects. Energy transfer continues until thermal equilibrium is reached (both objects at the same temperature).

What is the function of a clutch in a mechanical system?

Answer: To connect and disconnect the engine from the transmission

A clutch allows a driver to connect or disconnect the engine's rotating crankshaft from the transmission. This enables smooth starting from rest, gear changes, and stopping the vehicle without stalling the engine.