Answer to Question #174447 in Classical Mechanics for Rohan

Question

A solid sphere has a vertical tunnel cut in it. The sphere rotates about its diameter parallel to the tunnel. A particle is dropped in the tunnel which fits in the tunnel and  moves along its length. To analyse the motion of the particle from the frame of the sphere, you should use

(a) a centrifugal force but no coriolis force

(b) a coriolis force but no centrifugal force

(c) a centrifugal force and also a coriolis force

(d) neither a centrifugal force nor a coriolis force

Answer 1

In the rotating reference frame (or the frame of the sphere) there are two forces that act on the particle: the centrifugal force and the Coriolis force. Therefore, to analyse the motion of the particle from the frame of the sphere, you should use the centrifugal force and also Coriolis force.

Answer:

(c) a centrifugal force and also a coriolis force.