A particle A suffers an oblique elastic collision particle `B` that is at rest initially. If their masses with a are the same, then after the collision

A particle of mass m moving with velocity vecV makes a head on elastic collision with another particle of same mass initially at rest. The velocity of the first particle after the collision will be

A particle P moving with speed v undergoes a head -on elastic collision with another particle Q of identical mass but at rest. After the collision the collision

A ball of mass m moving with a velocity v undergoes an oblique elastic collision with another ball of the same mass m but at rest. After the collision if the two balls move with the same speeds , the angle between their directions of motion will be: