(adsbygoogle = window.adsbygoogle || []).push({}); 1. A 3 kg block slides down a 30 degree incllined plane with constant acceleration of 0.5 m/s2. The block starts from rest at the top. The length of the incline is 2m.

a) What is the velocity of the block at the bottom?

b) What is the magnitude of the normal force?

c) What is the coefficient of friction between the plane and the block?

I solved the questions, I'm just not sure if I got the answers right, so I wanted to double check with somebody here. For a) I got 2m/s (I forget how I got it, I didn't write down my work). For b), I did Fn = mg, and I got 29.4 N. For c), I did a diagram and got 13.3 N as the applied force. For Fnet, I did Fnet = ma, and got 29.4 N. Fnet = F applied - F opposing or friction, and I got -16.1 N as the force of friction (I'm not sure if having a negative force is possible, so if I'm wrong, just stay with me here). µ = Fs/Fn = -16.1N / 29.4N = -0.547. If any of this is wrong, please tell me how I was supposed to do it.

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# Homework Help: Forces and Friction

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