A ball with a mass of # 2 kg# is rolling at #25 m/s# and elastically collides with a resting ball with a mass of # 2 kg#. What are the post-collision velocities of the balls?
The velocities of the balls are
As the collision is elastic, there is conservation of linear momentum and conservation of kinetic energy
Let the velocity before collision be
Let the velocity after collision be
Here, we have