Find the acceleration of the block.

AI Thread Summary
To find the acceleration of the block in the pulley system, apply Newton's Second Law for both linear and rotational motion. The block's acceleration can be derived from the forces acting on it and the rotational inertia of the pulley. Using energy conservation, the height the block drops can be calculated based on its final speed. Additionally, constant-acceleration equations can verify the height obtained from energy conservation. The results from both methods should be consistent to confirm the calculations.
candyq27
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Hi. I really need some help with this problem. I don't even know where to begin. Please help guide me through it.

A pulley with a radius R=0.50m and a mass of M=4.0kg is mounted on a frictionless axle. The pulley is a uniform solid disk with rotational inertia I=1/2MR^2. A block with mass m=2.0kg hangs from a string wrapped around the pulley. When the system is released from rest the block accelerates down. Use g=10m/s^2.
a) After dropping through a height h, the block's speed is 2.0m/s. Using energy conservation, find h.
b) Apply Newton's Second Law and Newton's Second Law of Rotation. Solve your equations to find the acceleration of the block.
c) Use your value from (b) and one or more constant-acceleration equations to find h, the distance the block has dropped when its speed reaches 2.0m/s. Does it agree with your answer from (a)?
 
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Simply plug in x=0.
 
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