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

A 70-kg, starting from rest, is pulled across a floor with a constant horizontal force of 200 N. For the first 10 m the floor is frictionless, and for the next 10 m the coefficient of friction is 0.30. What is the final speed of the crate?

2. Relevant equations

W= -Delta PE

Wnc= DELTA PE+DELTA KE

F=ma

Ff=MuFn

W=Fd

3. The attempt at a solution

What I tried is to calculate the total work. So I calculate the work being done frictionless.

W=FD

W=200(10)

W=2000

Now I had to calculate work on friction

W=FD

W=(686)(.30)(10)

W=2058

This is how far I have gotten.

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# Homework Help: Conservation of Forces

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