A block A of mass M moving with speed u collides elastically with block B of mass m which is connected to block C of mass m with a spring. When the compression in spring is maximum, the velocity of block C with respect to block A is (Neglect the friction everywhere)

A block A of mass M moving with speed u collides elastically with bloc

1.	A block A of mass M moving with speed u collides elastically with block B of mass m which is connected to block C of mass m with a spring. When the compression in spring is maximum, the velocity of block C with respect to block A is (Neglect the friction everywhere)
Answer» ZERO `(M/(M+m))u` `(m/(M+m))u` `(m/M)u` Solution :`v_(A) = (M-m)/(M+m) u and v_(B) = (2MU)/(M+m)` Velocity of C at maximum COMPRESSION = `v_(B)/2` `v_(c) = 1/2[(2M)/(M+m)]u = (M/(M+m))u` `v_(CA) = v_(C)-v_(A) = (m/(M+m))u`