Welded discs dropped whilst string wrapped around one, find downward a

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The discussion focuses on calculating the force exerted by a block on a string while the block accelerates downwards. The key equation derived involves the relationship between gravitational force and tension, specifically 1.5g - T = 1.5a. The acceleration of the block is denoted as 'a', which is related to the angular acceleration through a = rα. The participant successfully arrives at the correct answer using these principles. Overall, the thread emphasizes the importance of understanding the dynamics of forces in this scenario.
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Image included to show I've made an attempt, but my attempt left me realising I just don't know where to go. If someone could point me in the right direction, it'd help a lot.
 
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You don't need to do energy calculations for this problem. One of the unknowns is the downwards acceleration of the block, and this affects the downwards force that the block exerts onto the string.

What is the equation for the force the block exerts on the string if the block is accelerating downwards at a, where a is the rate of acceleration of the block?
 
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rcgldr said:
You don't need to do energy calculations for this problem. One of the unknowns is the downwards acceleration of the block, and this affects the downwards force that the block exerts onto the string.

What is the equation for the force the block exerts on the string if the block is accelerating downwards at a, where a is the rate of acceleration of the block?

Ok, I got the correct answer this time, by using 1.5g - T = 1.5a, a=r\alpha, and \tau = rF :) Thank you!
 
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