(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A horizontal spring with spring constant 200 N/m is compressed 20 cm and used to launch a box across a rough horizontal surface. After traveling a distance it stops. What is the work done by friction force?

2. Relevant equations

[tex]W = F \cdot d[/tex]

[tex]KE_{spring} = \frac{1}{2}k \Delta x^2 [/tex]

3. The attempt at a solution

I don't know where to start, because I'm not sure what other relevant equations I can use. I'm thinking that the friction has to do enough work to make the box stop (v = 0). But I don't know how to relate the work by friction to the energy of the spring.

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# Homework Help: Work done by friction force

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