Rotating wheel with kinetic friction

[bradycat]

Hi,
The problem attached is a kinetic problem.
problem # 50.
This is from belts friction that this question is from.

All my other problems have dealt with static, and now with kinetic, I am stuck on what to do.

There is no impending motion that I know. Would I take the rope with the 45 degree angle as TL, and T=15 lbs as Ts?,

I do a moment on the pin of the wheel, and if so, not sure where to begin with that one.

Any help would be greatly appreciated, thanks
Joanne

 

[tiny-tim]

Hi Joanne!

You need to find the normal force per length, then multiply it by the length and by µ (and then by r for the torque ) …

do a free body diagram for a small bit of rope of length r dθ to find the normal force