Conservation of Momentum: Pulley System

AI Thread Summary
The discussion focuses on a physics problem involving a pulley system with two blocks, where block A is on a frictionless table and block B hangs off the edge. The participants analyze the linear acceleration of the system, using relevant equations like torque and moment of inertia. Despite one participant's confidence in their calculations, an online homework checker indicates their answer is incorrect, leading to speculation about potential errors in the professor's grading system. The conversation highlights the importance of verifying calculations and the challenges of online homework platforms. Overall, the participants express uncertainty about the accuracy of their results and the reliability of the grading system.
Watney
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Homework Statement


Block A (of mass MA) rests on a frictionless horizontal table. It is connected via a light string to block B (of mass MB) hanging over the edge of the table. The pulley itself, a solid disc, has non-negligible mass MC. The light string does not slip over the pulley.
What is the magnitude of the linear acceleration of the system?

Edit: Messed up with the title! This problem is in the chapter of Conservation of Momentum in my book but I actually didn't use it for this problem.

Homework Equations


Στ=Iα
α=a/r
Moment of Inertia of a disk = 1/2mr^2

The Attempt at a Solution


So here's my attempt but I'm not sure where I'm messing up.
FullSizeRender 2.jpg
 
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Your work looks correct .

Why do you think you are messing up somewhere ?
 
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Vibhor said:
Your work looks correct .

Why do you think you are messing up somewhere ?

When I enter my answer into my online homework answer checker, it says it's wrong. I'll have to ask my professor if maybe there's a mistake with his website cause sometimes he messes up!
Thanks though!
 
I don't know where you're messing up. I didn't see anything wrong.
 
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Watney said:
sometimes he messes up
That is probably what happened. I went through the problem twice and got the same result both times.

Acknowledging @Vibhor who answered before me. I didn't see it until after I posted.
 
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