Two blocks of mass connect to a pulley

AI Thread Summary
Two blocks of mass are connected by a massless string over a frictionless pulley, with one block sliding on a horizontal surface. The equations for acceleration and tension have been established, but the user is struggling with calculating the net torque on the pulley. It is clarified that the tensions from the two blocks will be different, leading to the equation τnet = r*T1 - r*T2. The user is advised to apply the rolling constraint a = rα to solve the problem. The user successfully resolves the issue after this guidance.
kitsunebell74
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Homework Statement



Blocks of mass and are connected by a massless string that passes over the pulley in the figure . The pulley turns on frictionless bearings, and mass slides on a horizontal, frictionless surface. Mass is released while the blocks are at rest.



Homework Equations



I found a1 for the mass of block one (m1).
a1 = m2g/(m1+m2)
T = (m1*m2*g) / (m1 + m2)
and tension in the string (which is the same everywhere)

The Attempt at a Solution



Now I must find a1 with a mass of the pulley (mp) and radius R.

So far I have drawn my free body diagrams for block 1, block 2, and the pulley. I was able to sum up my forces but I am having trouble summing up the net torque. Will the tensions from the two block be separated? Like this Tnet = r*T1 + r*T2
 
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welcome to pf!

hi kitsunebell74! welcome to pf! :smile:
kitsunebell74 said:
So far I have drawn my free body diagrams for block 1, block 2, and the pulley. I was able to sum up my forces but I am having trouble summing up the net torque. Will the tensions from the two block be separated? Like this Tnet = r*T1 + r*T2

yes, the tensions will be different, and τnet = r*T1 - r*T2

now apply the rolling constraint a = rα :wink:
 
Thanks for the greeting. I figured it out. :)
 
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