Masses over a Pulley (w/ angular kinematics)

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Cdh0127
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Homework Statement


http://imgur.com/koz4PpI
Physics diagram of two masses connected by a rope over a pulley: mA on the ground at left, mB resting 2.5 m above the ground at right, with the pulley labelled R0 above them.

Homework Equations

The Attempt at a Solution


I was able to calculate the net torque on the pulley as 55.88 and the Inertia as .352. Those could be wrong, but that's as far as I could get. I really have no idea. Any kind of help/explanation would be wonderful!
Handwritten work on a notepad page with a diagram of two masses on a pulley: mA = 34.0 kg, mB = 48.0 kg, pulley radius 0.40 m, mass 4.4 kg, 2.5 m drop; tension T = 133.2 N and 188.6 N; forces 470.4 N; I = 1/2 MR^2 = 0.352; sum of torques = I alpha giving alpha = 155.91 rad/s^2.
 
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Hi Cdh0127. Welcome to Physics Forums!

Please show details of what you've tried. Show us the formulas you've used and how you've applied them. It's hard to help you when we can't see what you're working with and what you've tried. Wrong answers don't tell us how they may have gone wrong.
 
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gneill said:
Hi Cdh0127. Welcome to Physics Forums!

Please show details of what you've tried. Show us the formulas you've used and how you've applied them. It's hard to help you when we can't see what you're working with and what you've tried. Wrong answers don't tell us how they may have gone wrong.

I just added a screenshot of my work. I hope you can make sense of it xD
 
Cdh0127 said:
I just added a screenshot of my work. I hope you can make sense of it xD
You'd be better off laying out your work in text in a post, explaining the steps. That way helpers can quote the lines and point out issues. Otherwise you're expecting them to forensically untangle where you started and what you did from the scatter of notes on the image. You're really limiting the number of helpers who'll be willing to make the effort that way.
 
Just to add my 2 cents from a quick perusal of your diagram, it doesn't appear that you went anywhere with the conservation of energy approach suggested in the problem statement. You went after torques and forces instead.

Rethink your approach. Where does the energy come from to make the system move? How much energy is made available from the initial position to the final position? Where does it go?