A horizontal force of 100N pushes a 12kg block up a frictionless(adsbygoogle = window.adsbygoogle || []).push({});

incline that makes an angle of 25 degree with the horizontal. a)

what is the normal force that the incline exerts on the block? b)

what is the acceleration of the block?

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I don't know when to chose the force of the x axes or the y axes.

After drawing a free body diagram I get really lost when the cos and sin are switched. for example, when Fy = cos F instead Fy = sin F.

I know this is easy, but I am trying to pinpoint the pit falls so I can master the concept. I thank you all in advance.

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I draw a freebody diagram and taking x=axes to be forming 25 degree with the theta.

Sigma Fy = Fny + Wy + Fy = May

Fny - W + F sin(25) = 0

Fn = 12(9,81) - 100(sin 25)

Fn = 75.5N

Please help me

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# Homework Help: Newton's laws

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