Understanding Angular Acceleration and Velocity in Pulley Systems

AI Thread Summary
The discussion focuses on calculating angular acceleration and velocity in a pulley system where a weight falls with a constant acceleration of 3.10 m/s². The angular acceleration of the pulley, derived from the linear acceleration, is found to be 95.4 rad/s². For the second part, the angular velocity of the pulley when the weight hits the floor is also calculated to be 95.4 rad/s, leading to confusion about why both answers are the same. The participant seeks clarity on the relationship between linear and angular motion in this context. Understanding the equations and their application is key to resolving the confusion regarding the results.
mike.yeagley2
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The question I am given is as follows:

A string is wrapped around a pulley of radius 3.25cm, and a weight hangs from the other end. The weight falls with a constant acceleration 3.10m/s^2.

1. What's the angular acceleration of the pulley?
2. If the weight starts from rest 1.55m above the floor, what's the pulley's angular velocity when the weight hits the floor?

My issue is with the equations I have available to me.

Equations: Angular Acceleration=Δω/Δt Angular Velocity=Δθ/Δt w=2pi/t and the equivalent translational versions for the weight in question 2.

I am looking to understand how to formulate the correct equations to get the answer. Any help would be appreciated.
 
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Is that homework?
 
Yes it is. I found the equation I needed for Part one with linear acceleration, and that makes sense. The answer was 95.4rad/s^2, but the answer was the same for the second question as well, and I don't fully understand that. I am looking to understand why it is the same answer.
 
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