A particle of mass `2kg` moving with a velocity `5hatim//s` collides head-on with another particle of mass `3kg` moving with a velocity `-2hatim//s`. After the collision the first particle has speed of `1.6m//s` in negative x-direction, Find
(a) velocity of the centre of mass after the collision,
(b) velocity of the second particle after the collision.
(c) coefficient of restitution.

Explanation

(i) `v_(c) = (m_(1)u_(1) + m_(2)u_(2))/(m_(1) + m_(2)) = 0.81 hat(i)ms ^(-1)`
[Velocity of CM before and after collision will be same]
(ii) `v_(i) = -1.61 hat(i) ms^(-1)`
From CM, `m_(1)u_(1) + m_(2)u_(2) = m_(1)v_(1) + m_(2)v_(2) rArr v_92) = 2.4 hat(i) ms^(-1)`
`e = (v_(2)-v_(1))/(u_(1)-u_(2)) = 4/7`