Question

A ball with a mass of `400 g` is projected vertically by a spring loaded contraption. The spring in the contraption has a spring constant of `64 (kg)/s^2` and was compressed by `3/4 m` when the ball was released. How high will the ball go?

Answer 1

Taking `g=10`[m/s²] we obtain `h = 4.5`[m]

Explanation:

The spring mechanical energy `E_m = 1/2Kx^2` is transformed in potential energy for the ball `E_p = m g h`. Equating both energy forms we get
`1/2Kx^2=m g h`
Solving for `h = 1/2Kx^2/(m g)` with `g = 10` we get
`h = 4.5`[m]