I can't figure out what I did wrong on this test question.(adsbygoogle = window.adsbygoogle || []).push({});

A 4kg block is dropped from a height of 0.8m above a spring, k=120N/m. Find the maximum compression of the spring.

I have the PE at the top is equal to KE at the bottom.

PEtop=31.4J

KEbottom=31.4J

The potential energy in the spring when compressed should equal the KE at the bottom. Based upon that I should be able to find the maximum distance the spring will compress.

KEbottom=Wspring

31.4J=.5*120*x^2

Rearranging x=sqrt(2*31.4/120) and I get x=-0.723m

What am I doing wrong here? Can someone point it out.

Thanks, peace

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# Homework Help: Test Question (Potential Energy): Need help finding answer

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