Solving Dynamics Homework Problem: Ceiling Force on Hook

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To solve the dynamics problem involving a pulley and two weights, start by drawing free body diagrams for the weights and the pulley, considering all acting forces and torques. The system includes a 50 N frictionless pulley with a radius of 0.300 m, supporting a hook connected to the ceiling. The weights are 75 N and 125 N, leading to a net force that the ceiling must counteract. By applying the equations of motion, specifically F = ma, and accounting for the moment of inertia of the pulley, the force exerted by the ceiling on the hook can be calculated as 249 N. Understanding the forces and torques is crucial for finding the correct solution.
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Homework Statement



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.



Homework Equations


I = 1/2 MR^2
F=ma



The Attempt at a Solution


clueless..help!
 
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J89 said:

Homework Statement



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.



Homework Equations


I = 1/2 MR^2
F=ma



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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