Find Mass of Pulley in Atwood's Machine Homework

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To find the mass of the pulley in an Atwood's machine, the conservation of energy principle should be applied, considering both gravitational potential energy and rotational kinetic energy. The initial energy is derived from the height of mass m1, while the final energy includes the kinetic energy of both masses and the rotational energy of the pulley. The acceleration of the system can be calculated using the formula a = [(m1 - m2)/(m1 + m2)]g, which relates the masses and gravity. The problem highlights the need for clarity in formulating questions, as the initial post lacked a specific inquiry. Understanding these concepts will guide the solution to determining the pulley's mass.
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Homework Statement


The two masses (m1 = 5.2 kg and m2 = 2.6 kg) in the Atwood's machine shown in The Figure are released from rest, with m1 at a height of 0.79 m above the floor. When m1 hits the ground its speed is 1.7 m/s.

Assuming that the pulley is a uniform disk with a radius of 12 cm, outline a strategy that allows you to find the mass of the pulley.

Determine the pulley's mass.

Homework Equations


Rotational Kinetic Energy: K + (1/2)Iw2
Conservation of Energy: Ki + Ui = Kf + Uf

The Attempt at a Solution


I am more or less stumped on this problem. Information that is known is that v0 = 1.7 m/s and vf = 0. The Ei = mgh (I think since the system starts at rest and m1 has Gravitation Potential Energy). Ef = (1/2)mv2 + (1/2)Iw2. All this is speculation since I am grasping at a way to solve this problem.

Also, from looking at other related problems people tend to find acceleration through the Kinematics v2 - v02/2(x - x0). However, I am not sure how to apply the acceleration of m1, all I know is that it translates through the pulley system.

Another possible acceleration I found was a = [(m1 - m2)/(m1 + m2)]g. This formula brought up a different acceleration than the previous, but once again I am not certain how to apply it.

Reassurance that I am on the right route, and a hint would be greatly appreciated.
 
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What is the question? Your problem is nothing but stated facts, and there is no question. Literally, not a single question mark.
 
Thank you for bringing that to my attention. I have spent so much time belaboring the issue through my mind that I completely forgot to actually spell out the question.

Although, no question marks does not mean there exist no questions.
 
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