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## Homework Statement

See the this link for problem statement, http://i48.tinypic.com/vphsm1.jpg

Case 1 I've solved, however I'm unsure about how good my solution is for case 2.

## Homework Equations

F=ma Fu = N * uk

## The Attempt at a Solution

Ok first I sum the forces in the y direction orientated about the log so my y direction is normal to the log.

N - 400(9.81)cos(a) = 0

then i do a force summation in the x direction.

0.5*N -2T +400*9.81sin(a)=0

next I do a force summation on block A in the upward direction, where the downward direction is positive,

125(9.81)-T = 0

so T =1226.25 N

Now this where i get stuck.

I have two equations with two unknowns but can't solve for a. my attempt is as follows:

N=400*9.81*cos(a)

then i sub this into 0.5*N -2T + 200*9.81sin(a)

to get 1962cos(a) -2452.5 + 3924sin(a) =0

but i cannot solve this equation for a.

Any tips on where I'm going wrong would be greatly appreciated. Thanks!

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