# Dynamic motion involving pulleys and friction.

#### DaftCrunk

1. The problem statement, all variables and given/known data
http://img689.imageshack.us/img689/2315/dynamicsproblem.jpg" [Broken]

2. Relevant equations

3. The attempt at a solution

FC = FfB
mC * 9.81 = (6.0)(9.81)(0.30)
mC = 1.8 <---- :(

Obviously that was wrong haha. I then tried to figure out how the pulley affects the relationships of the forces, and figured:

FfB = MC(9.8-aA)
17.6 = MC(9.8-aA) <-----One equation, two unknowns. Need another equation, assuming this one is correct.
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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#### tiny-tim

Science Advisor
Homework Helper
Welcome to PF!

Hi DaftCrunk! Welcome to PF! … Need another equation, assuming this one is correct.
Yup! … try F = ma for A-and-B. ### Physics Forums Values

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