Question

Problems based on conservation of angular momentum

Answer 1

In an isolated system the moment of inertia of a rotating object is doubled. What happens to angular velocity of the object?

If the system is an isolated one, no net torque acts on the object. Thus the angular momentum of the object must remain constant. Since L = Iσ, if I is doubled, σ must be halved. Thus the final angular velocity is equal to one half its original value.