A body of 1 kg moving at 4 m/s strikes a stationary body of 750 g. The first body stops and the other moves at 5 m/s. What is the coefficient of kinetic friction.

Asked on by lxsptter

1 Answer | Add Yours

justaguide's profile pic

justaguide | College Teacher | (Level 2) Distinguished Educator

Posted on

A body of mass 1 kg is moving at 4 m/s and it collides with a stationary body with a mass of 750 g or 0.75 kg. After collision, the first body comes to a stop and the second moves at 5 m/s.

If friction could be ignored here, the law of conservation of kinetic energy would ensure that total kinetic energy is conserved. As the total initial kinetic energy is 1*4^2 = 16 J, the total final kinetic energy would be 16 J too. But the total final kinetic energy is 0.75*5^2 = 0.75*25 = 18.75 J. It is seen that due to the collision the total kinetic energy in the system has increased by 2.75 J.

This is not possible in an isolated system.

There is an error in the information provided by you.

We’ve answered 319,818 questions. We can answer yours, too.

Ask a question