Finding the magnitude of acceleration

[Include]

Homework Statement

Problem one on this pdf file.
http://www.dtfizzix.com/APEXAMS/Phackets/B-1987-Exam.pdf

Homework Equations

F=ma
ΣFx= ma

The Attempt at a Solution

ΣFx= (m1+m2)a

What are the total forces on of the block labeled M1?

 

[1MileCrash]

Tension, and friction, in opposite directions. To find tension, look at block B. To find friction, multiply the normal force by the coefficient of friction. Since there is no vertical acceleration of block A, that means that there must be no net vertical force, so what does this say about the normal force?

 

[Include]

Tension, and friction, in opposite directions. To find tension, look at block B. To find friction, multiply the normal force by the coefficient of friction. Since there is no vertical acceleration of block A, that means that there must be no net vertical force, so what does this say about the normal force?

That the normal force must equal the gravitational force?

I've solved the problem (a) and (b).

Now I need help with problem (c). What are the total forces acting on M1?

Is it the mass of M2 minus the coefficient of friction of M1?

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