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

You apply a constant force F=(-68.0N)i + (36.0N)j to a 390kg car as the car travels 60.0m in a direction that is 240.0° counterclockwise from the x-axis.

How much work does the force you apply do on the car?

2. Relevant equations

W=Fs

W=K2-K1

W=Fcos(θ)s

F/m=a

Vf^2=Vi^2 + 2Ad

3. The attempt at a solution

Im not sure what I am doing wrong here. I have calculated the magnitude of the Force as 76.9N.

So I have tried:

76.9(cos(240))*-60 (applying the force in the same direction as the car moves) = 2307J

I also tried to use the Work energy theorem and found acceleration (76.9/390kg)=0.197m/s^2. I then used this in Vf^2=Vi^2 + 2Ad. So Vf = 4.86. I then use that in K2-K2=W=.5mVf^2-.5Vi^2. (I was assuming that Vi is 0 here, even though it didn't state from rest)

I feel like this is something simple that I am missing. Any direction would be great!

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# Homework Help: University Physics 1 Work Problem

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