Rotational Motion- Pulleys with Friction

AI Thread Summary
The discussion revolves around calculating the acceleration of two suspended masses connected by a pulley that experiences friction. The user is attempting to solve the problem using the equations of motion and torque but is struggling with the differing tensions in the cords due to friction. They have derived a formula for acceleration but are unsure how to incorporate the torque from the pulley into their calculations. The key equations include those for tension, torque, and moment of inertia. Assistance is requested to clarify how to effectively apply the torque in the context of the problem.
danield
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Homework Statement


Two Masses are suspended from a pulley. The pulley itself has a mas of .20kg a radius of .15m a constant torque of .35 MN due to the friction between the rotating pulley and its axle. What is the magnitude of the acceleration of the suspended masses if m1= .4kg and m2= .8 kg (neglect the mass of the string)
Pulley
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M2 M1




Homework Equations


T1= M1G - M1A
T2= M2G + M2A
Torque= FL = Moment of Inertia x Alpha,
I= 1/2 mr^2

The Attempt at a Solution


I have tried solving this by solving for A when T2-T1= I alpha, but i really don't know how to apply the fact that the tension is different of both cords due to the friction on the pulley I am stuck...
 

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I have tried everything... but still i can't get to the answer.. i get to the formula a=(m2-m1)g/(1/2M+m1+m2) but after that i don't know how to apply the torque... :( need help
 
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Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...

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