- #1

awelex

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## Homework Statement

A 0.150-kg frame, when suspended from a coil spring, stretches the spring 0.050m. A 0.200-kg lump of putty is dropped from rest onto the frame from a height of 30.0m.

mass of frame: mf

mass of putty: mp

height: h

## Homework Equations

## The Attempt at a Solution

I tried the following, which was wrong:

0.150 * 9.8 = k * 0.050 --> k = 29.4

velocity of putty when it touches frame:

0.200*g*0.3=(1/2)*0.200*v^2 --> v^2 = 2hg

(1/2)(mp+mf)*v^2 = (1/2)*k*x^2

--> x = 0.2m

So the final answer is either 0.2m or 0.25m (depending on whether one adds the initial 0.05m). Both answers are wrong, though. What am I doing wrong?

Thanks.