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

- Taken directly from the homework -

- Attachment has the diagram -

Body A in Fig. 6-33 weighs 100 N, and body B weighs 78 N. The coefficients of friction between A and the incline are μs = 0.54 and μk = 0.22. Angle θ is 29°. Let the positive direction of an x axis be down the slope. What is the acceleration of A if A is initially (a) at rest, (b) moving up the incline, and (c) moving down the incline?

3. The attempt at a solution

My problem is in figuring out which equations to setup. My initial thoughts are as follow:

a) figure out the acceleration of the system, then factor in friction after finding which direction the block wants to travel.

F_{netA}= sin(29)100N - T

F_{netB}= T - 78N

b) This didnt account for friction right off, so I modified for this:

F_{netA}= sin(29)100N - T - (100N)(0.54)(cos(29))

F_{netB}= T - 78N

a & b) Once having these equations, I set them up to equal T, then set F_{netA}(solved for T) equal to F_{netB}(solved for T).

This still didn't really seem to yield any insight. Please help me realize how to setup these initial equations and I'm sure the rest will fall in place.

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Acceleration on incline (w. Friction)

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