# Colliding again

**Classical Mechanics**Level 4

On a horizontal frictionless circular track of radius R, lie two small masses m and M, free to slide on the track. Between the two masses is squeezed a spring which, however, is not fastened to m adnd M. The two masses are held together by a string.

If the string breaks, the compressed spring shoots off the two masses in opposite directions, spring itself is left behind. The balls collide when they meet again on the track.

Where does this collision take place?

Expressed your answer as the angular displacement of M.

Your answer will be of the form a(pi)/b

Find the value of a*b

DETAILS :

1- M=300 kg

2- m=250 kg

3- a, b are coprime natural numbers