Rotational Inertia: Solve for Acceleration of Suspended Masses

AI Thread Summary
The discussion revolves around calculating the acceleration of two suspended masses in a pulley system, factoring in the pulley’s rotational inertia and friction. The provided equations relate torque, rotational inertia, and angular acceleration, with an initial calculation yielding an angular acceleration of 233.333 rad/s². Participants highlight the need to consider both the torque due to friction and the tension in the strings when applying Newton's laws. There is a request for clarification on how to integrate the masses into the calculations effectively. The conversation emphasizes the importance of accurately applying the principles of rotational dynamics to solve for linear acceleration.
annamae
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Homework Statement


Two masses are suspended from a pulley system. The pulley itself has a mass of .2kg, a radius of .015m, and a constant torque of .35Nm due to friction between the rotating pulley and its axle. What is the magnitude of acceleration of the suspended masses if m1=.4kg and m2 = .8kg?


Homework Equations



Torque=I(rotational inertia) * angular acceleration
I= 1/2* m * r2


The Attempt at a Solution


T=I*a
.35= (.5)(.2)(.0152)(a)
233.333=angular acceleration

233.333/.015=3.5
3.5=linear acceleration

What do I do with the masses?
Is all that above work right?
 
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T = Ia is for T(total) you have just taken T due to friction
also use the T due to tension in strings ...

and for masses find net acceleration using newon's laws and find tension in 2 strings ... then apply T=Ia
 
could you maybe explain that with a bit more detail, I am still not sure of what to do
 

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