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

Body A weighs 110 N, and body B weighs 37 N. The coefficients of friction between A and the incline are μs = 0.56 and μk = 0.25. Angle θ is 40°. Let the positive direction of an x axis be up the incline.

(a). Find the acceleration of A if A is initially at rest.

(........ m/s^2) i

(b). Find the acceleration of A if A is moving up the incline.

(.........m/s^2) i

(c). Find the acceleration of A if A is moving down the incline.

(.........m/s^2) i

2. Relevant equations

F=ma

3. The attempt at a solution

So I am not really sure how to solve this problem at all. I have tried a few ways, none have come up with reasonable or correct answers.

I tried using...

F_{T}= m_{A}* g * sin(theta) - f_{k}

where f_{k}= mew_{k}* F_{N}

and setting F_{N}= g * a

I then solved for a and came out with 134 but that was wrong and didn't make sense.

I have no idea what to do next. Can anyone help me out? That would be awsome.

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# Homework Help: Properties of Friction

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