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

A crate of mass 20 kg is pushed up a ramp by a person, at an angle of 30 degrees. Assume the coefficient of kinetic friction between the crate and the ramp is k=0.2. Calculate the work done by the person in pushing the crate a distance of 29 m as measured along the ramp. Assume that the crate moves with at a constant velocity.

2. Relevant equations

W=mgh

W=F(delta x)cos(theta)=(coefficient of friction)mg(delta x)cos(theta)

3. The attempt at a solution

I found the work due to normal force to be 0, then used the first equation to find the work due to gravity. W=(20kg)(9.8m/s^2)(14.5m)=2842 Next I used the second equation to find the work due to the friction. W=(.2)(20)(9.8)(25.1147)cos(30)=852.59875

I added these two numbers together since the person would have to do work against gravity and the friction and got 3694.59875, but this isn't the right answer. Anyone have help for me? I am thinking my equations might not be right.

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# Homework Help: Crate Pushed up an Incline

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