Question

In experiment 1 ( Moment of inertia), when changing the mass of the weight and the radius of the step pulley, how does the magnitude of the moment of inertia change?

Answer 1

Moment of inertia of a body is the torque required to give it angular acceleration. It is analogous to the mass in linear motion, as for mass we need force to give it linear accleration.

For a body moment of inertia depends upon the mass distribution of the body and their distance from the axis of rotation., where I is Moment Of Inertia. For a point body it is given by I = mr².

So, changing the mass of the body ( mass distribution) or radius of the body (also mass distribution change) will change the moment of inertia according to above formula.