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I am having trouble answering this question.

The drawing shows a block against a vertical wall to its right. The force F is pointed at the lower left hand corner of the block at 40.0 deg. left of -y-axis

The weight of the block in the drawing is 88.9N. The coefficient of the static friction between the block and the vertical wall is 0.560. a)What minimum force F is required to prevent the block from sliding down the wall? b) What minimum force F is required to start the block moving up the wall?

Here is my attempt at it--

a) Fs(max)=(0.560)(88.9N)=49.8N

Fy=88.9N-49.8N=39.1N

Fx=(39.1N)/(cos(40))=51.0N

sqrt{39.1^2+51.0^2}=F

F=64.3N

b) 88.9N +49.8 N=138.7N=Fy

Fx=(138.7N)/(cos(40))=181.06N

sqrt{138.7^2+181.06^2}=F

F=228N

But it doesn't seem right!

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# Homework Help: Can someone please help! Equilibrium/friction

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