Question

The role of ____________ in rotational motion is same as the role of mass in linear motion

• A. Torque
• B. Acceleration
• C. Moment of inertia
• D. Velocity

Answer 1

Answer:

C. Moment of inertia

In rotational motion, the role of moment of inertia is similar to that of mass in linear motion. Moment of inertia expresses a body's tendency to resist angular acceleration. It depends on mass distribution, shape, and size of the body, and the axis of rotation. It is calculated as the sum of the moments of inertia of all particles taken about the same axis. When the mass is situated close to the axis, moment of inertia is small, and when it is situated at a large distance, it is large. The equation for moment of inertia for point mass is $l = m r^2$