(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Figure shows a block of mass m resting on a 20* slope. The block has coefficients of friction uS=0.80 and uK=0.50 with the surface. It is connected via a massless string over a massless, frictionless pulley to a hanging block of mass 2.0 kg.

Part A:

What is the minimum mass m that will stick and not slip?

Part B:

If this minimum mass is nudged ever so slightly, it will start being pulled up the incline. What acceleration will it have?

2. Relevant equations

Fnet=ma

us=F/N

3. The attempt at a solution

I really have no idea how to do Part B, but I tried part A and was real confident with my answer but it turned out wrong. This is what I did.

(2kg)(9.8)=19.6N for the hanging mass

assuming that the Hanging mass = to the tension force on the block with mass m I then did this...

19.6N=m(9.8)cos20*(.8)

m=2.66kg and this is wrong

Were did I go wrong?

Thanks

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# Homework Help: Mass on incline will it slip or stick?

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