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

NOTE: Use the local value of g = 9.809 m/s2

You and your roommate are dragging an exercise machine (mass 56.9 kg) down a 71.2 meter long hall, from the stair landing, where (because of union rules) the UPS driver left it, to your dorm room. The coefficient of friction with the floor is μ = 0.866. The mechanical work you do in the process is:

2. Relevant equations

ME=GPE+KE

GPE=mgy

KE=1/2 mv^2

F(friction)=mu*N

N=mg

F=ma

W=Fd

3. The attempt at a solution

I tried solving for the gravitational potential energy and then solving for the frictional force and multiplying the result by the distance...looking back on it, I'm fairly sure that it was probably the wrong method to go about this problem. I know that the mechanical energy is the sum of the potential energy and kinetic energy. However, if that is the case, I would have to solve for velocity and I am not sure how to do that with the information given. When I try to use the 2-d equations, I end up with two variables (v and vo). It would really help if I could get some help (and reasoning) about solving this problem.

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# Homework Help: Mechanical energy

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