Which quantity in rotational motion is analogous to force in linear motion ? a) Torque b) Moment of inertia c) Angular velocity d) Angular momentum

In rotational motion, torque is the quantity analogous to force in linear motion.

Explanation:

• Force in linear motion causes acceleration and changes the state of motion of an object.
• Similarly, torque in rotational motion causes angular acceleration and changes the rotational state of an object.
• Mathematically, force $F=ma$ (Newton’s second law) has its rotational counterpart in torque $\tau =I\alpha$, where:
  • $\tau$ = torque (analogous to force),
  • $I$ = moment of inertia (analogous to mass),
  • $\alpha$ = angular acceleration (analogous to linear acceleration).

Thus, torque is the correct answer.