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Dynamics question

  • Thread starter J89
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J89

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1. The problem statement, all variables and given/known data

Two weights are connected by a very light flexible cord that passes over a 50 N frictionless pulley of radius .300 m. Pulley is a solid uniform disk and is supported by a hook connected to a ceiling. What force does the ceiling exert on the hook? There are two weights around each side of the disk, one is 75 N and the other is 125 N. Answer is 249 N.



2. Relevant equations
I = 1/2 MR^2
F=ma



3. The attempt at a solution
clueless..help!
 
1. The problem statement, all variables and given/known data

Two weights are connected by a very light flexible cord that passes over a 50 N frictionless pulley of radius .300 m. Pulley is a solid uniform disk and is supported by a hook connected to a ceiling. What force does the ceiling exert on the hook? There are two weights around each side of the disk, one is 75 N and the other is 125 N. Answer is 249 N.



2. Relevant equations
I = 1/2 MR^2
F=ma



3. The attempt at a solution
clueless..help!
As in any dynamics problems, start by drawing out your free body diagrams for each body - your two weights and the pulley, taking into acount all the forces acting on the weight, and the sources of torque for the pulley.

Then you can apply F = ma to each body, for each axis of movement, but don't forget your appropriate constraints.
 

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