Question

Jasmine and Everett are playing pool in Jasmine's basement. On Jasmine's turn, a cue-ball was in motion at 2.07 m/s when it collide head on with the 2-Ball moving in the same direction at 1.43 m/s. Assuming identical mass balls and a perfectly elastic collision, what was the speed of the cue-ball after the collision?

Answer 1

After an elastic collision between two balls of identical mass, the cue-ball moving at 2.07 m/s will have a post-collision speed of 1.43 m/s, which was the initial speed of the 2-Ball.

Step-by-step explanation:

In a perfect elastic collision between two balls of identical mass where one ball (the cue-ball) moving at 2.07 m/s collides head-on with another ball (the 2-Ball) moving in the same direction at 1.43 m/s, the velocities of the balls will swap after the collision if they have identical masses. This is due to the conservation of momentum and kinetic energy, which are both preserved in elastic collisions. Thus, after the collision, the cue-ball will be moving at 1.43 m/s, and the 2-Ball will be moving at 2.07 m/s.