In an elastic collision of two billiard balls, the total kinetic energy is conserved?
For a short duration
For a long duration but not completely
None of Above
Answer: Option B
During the short time of collision when the balls are in contact, the kinetic energy of the balls gets converted into the potential energy. In an elastic collision, though the kinetic energy before the collision is equal to the kinetic energy after the collision but kinetic energy is not conserved during the short time of collision.