Conceptual torque problem with multiple sized pulleys

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crybllrd
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Homework Statement


This is a six part conceptual question that is not difficult. However, the last part I am struggling with.
What is wrong with the following student's reasoning:
"The clockwise torque is greater than the counterclockwise torque because the disk is accelerating clockwise. For this to happen, T2 must pull harder on the disk than T1."

Here's a pic I drew:

Diagram of a pulley with three concentric circles, two hanging strings labelled T1 and T2 on either side, and blocks labelled M1 and M2 hanging from their ends.


The Attempt at a Solution



Well I know the first sentence is correct.
But I also thought the second one is too.
A free body diagram would show m1 accelerating up, and m2 down. Therefore tension in
T1>T2.
What am I missing here?

EDIT: m1=m2
 

Discussion

It is correct that T1 must be greater than T2 if m2 accelerates downward. The reasoning is wrong. To accelerate the disk clockwise, the torque of T2 has to be greater than the torque of T1. How is torque defined?

ehild