Question

Which of the following best describes a completely elastic collision?

The potential energy ( U) of the system before the collision equals U after.
The kinetic energy ( K) of the system before the collision is less than K after.
The kinetic energy ( K) of the system before the collision is greater than K after.
The kinetic energy ( K) of the system before the collision equals K after.

Answer 1

D) The kinetic energy ( K) of the system before the collision equals K after.