Three Masses - pulley, rotational and translational forces

AI Thread Summary
The discussion centers on a mechanical system involving a green hoop, a blue disk pulley, and an orange sphere, all connected by a string. The hoop, which has a mass of 2.4 kg, descends while the pulley rotates, creating a relationship between the tensions on either side of the pulley. The net torque on the pulley is influenced by the falling hoop, and the sphere rolls without slipping, requiring consideration of friction at the contact point with the surface. The participants emphasize the importance of free body diagrams to analyze forces and torques in the system. Understanding these dynamics is crucial for calculating the linear acceleration of the hoop.
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An green hoop with mass mh = 2.4 kg and radius Rh = 0.18 m hangs from a string that goes over a blue solid disk pulley with mass md = 2.4 kg and radius Rd = 0.09 m. The other end of the string is attached to a massless axel through the center of an orange sphere on a flat horizontal surface that rolls without slipping and has mass ms = 3.3 kg and radius Rs = 0.25 m. The system is released from rest.

1)What is magnitude of the linear acceleration of the hoop?

I'm wondering how to solve this question, especially wondering how the tension forces would be related to each other throughout the system?
 

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From what is written, the hoop is not rotating - so it is just a mass falling: you can do the free body diagram for that one.

The pulley rotates, the net torque on the pulley will have it accelerate consistently with the acceleration of the falling mass. Label the tensions on each side of the pulley differently.

The sphere is rotating, the tension acts through the center, but there is a force from friction (rolling without slipping) where there is contact with the table. Just think of it as a wheel being pulled by the axle - you will have course notes for that situation.
 
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