A `2 kg` mass moving on a smooth frictionless surface with a velocity of `10 ms^(-1)` hits another `2 kg` mass kept at rest, in a perfect inelastic collision. After collision, if they move together

A 2 kg mass moving on a smooth frictionless surface with a velocity of 10 mshits another 2 kg mass kept at rest in an elastic collision. After collision, if they move together

A ball of mass 4 kg moving on a smooth horizontal surface makes an elastic collision with another ball of mass m at rest in the line of motion of first ball. If after collision first ball moves in the same direction with one fourth of its velocity before collision, then mass of second ball is

A ball of mass 4 kg moving on a smooth horizontal surface makes an elastic collision with another ball of mass m at rest in the line of motion of first ball. If after collision first ball moves in the same direction with one fourth of its velocity before collision, then mass of second ball is

A marble going at a speed of 2 ms^(-1) hits another marble of equal mass at rest. If the collision is perfectly elastic, then the velocity of the first marble after collision is