What Are the Limits of m1 to Prevent System Acceleration with µ=0.42?

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Homework Statement



What are the minimum and maximum values of m1 in the figure to keep the system from accelerating? Take µs = µk = 0.42.

5-30.gif


________ kg < (or equal to) m1 < (or equal to) ________ kg


Homework Equations



F = m(a)
Ff=Mk(N)
Ff=Ms(n)

The Attempt at a Solution



Fy(net)=0=Fn-Fgy
Fgy=Fgcos30
Fg=9.8m
Fn=9.8mcos30

Ff=.42(9.8mcos30)

Does Ff equal 49 since Fg of mass 2=49 and thus Ft must equal 49 so mass 2 doesn't move and then that means the Ft on the mass 1 also equals 49 so Ff must also equal 49??

49=.42(9.8mcos30)

I get m=13.75 which is wrong. :(
 
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You didn't write the net force along the diagonal direction. If you did, you'd notice that something was missing.