Question

In an in-class demo, I sat on a stool with a spinning bike tire. I was initi the spinning bike tire and I began to rotate. Explain whether the following quantities constant during this process. ally at rest. Then, I flipped over change or remain Angular Momentum of the bike tire Moment of Inertia of the bike tire Angular Momentum of the system of the bike tire and me Kinetic Energy of the system of the bike tire and me

Answer 1

A) Angular momentum of the bike tire-

The angular momentum of the bike tire remains constant as the angular momentum is the moment of inertia times angular velocity. So when person flip over the wheel the effective mass increases but angular velocity decreases by the same ratio so the angular momentum of the bike tire conserves.

B) Moment of inertia of the bike tire-

The moment of inertia of the bike tire increases because it is the ratio of the angular momentum with the angular velocity and here the angular momentum of the bike tire is constant and angular velocity decreases so we get a gain to tha moment of inertia of the bike tire.

C) Angular momentum of the bike tire and me -

The angular momentum of the whole system always remains conserve. In any case if one lose the angular momentum, the other one will gain the same amount. But the total angular momentum remains constant.

D) Kinetic energy of the system of bike tire and me -

The kinetic energy of the system is directly proportional to the magnitude of angular momentum and inversely proportional to the moment of inertia here we have constant angular momentum and a gain in the moment of inertia so the kinetic energy of the system will decrease as comparison to before.