- #1

TachyonLord

- 54

- 6

## Homework Statement

A “superball” of mass m bounces back and forth with speed v between two parallel walls, as shown. The walls are initially separated by distance l. Gravity is neglected and the collisions are perfectly elastic.

If one surface is slowly moved toward the other with speed V, the bounce rate will increase due to the shorter distance between collisions, and because the ball’s speed increases when it bounces from the moving surface.

__Find the average force at distance x.__## Homework Equations

$$\int\vec F \cdot \vec dx= ΔK$$

where ΔK is the change in kinetic energy

$$K = \frac {1} {2}mv^2$$

## The Attempt at a Solution

I tried using momentum conservation and the above equation, but I seem to get stuck, and my brain goes blank.