# Block falling on Spring

1. Oct 12, 2004

### Hughey85

A 2.0 kg block is falling at a speed of 11 m/s and is 18 meters above the spring. The spring constant is 4000 N/m, to the nearest hundredth of a meter what height will the block rise after it hits and leaves the spring?

Help please! I can find the kinetic energy of the falling block by using... K=.5mv^2 ..... I don't know how to go from there! Help!

Last edited: Oct 13, 2004
2. Oct 13, 2004

### Leong

Law of conservation of energy :
The total energy at the beginning = The total energy at the end
$$\frac{1}{2}mv^2+mgh_1=mgh_2$$
where
v=the block initial speed(initial state)
h1=the block height relative to the spring(initial state)
h2=the maximum height the block will reach (relative to the spring)ie v =0 (final state)