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## Homework Statement

[/B]A block with mass m1 = 9.2 kg is on an incline with an angle θ = 36° with respect to the horizontal. For the first question there is no friction, but for the rest of this problem the coefficients of friction are: μk = 0.33 and μs = 0.363.

1.) When there is no friction, what is the magnitude of the acceleration of the block?

2.) Now with friction, what is the magnitude of the acceleration of the block after it begins to slide down the plane?

## Homework Equations

F=MA

Force of Gravity: F

_{g}=-Mg

Normal Force: N = Mg

## The Attempt at a Solution

I'm so confused. For question 1, I found the acceleration to be 5.77 m/s

^{2}by finding the X-component of the normal force (53.05 N) and dividing by 9.2 kg. According my homework program, this is correct. However I don't really understand why.

My work:

F

_{x}= sinθ(mg)

F

_{x}= sin36(9.2*9.81)

F

_{x}= 53.05 N

A = F/M

A = 53.05/9.2

A = 5.766 m/s

^{2}

For question 2, I've tried a couple of different things with no success. I don't even remember them all. I've just been floundering about for an hour. I'd appreciate any help.