Rotational Motion Homework: Angular Momentum and Tension

AI Thread Summary
In the discussed lab, a weight tied to a string causes a wheel to turn when released. The first question addresses whether angular momentum is conserved; the response suggests it is not due to gravity accelerating the system. The second question about tension in the string concludes that it remains constant, equating to the weight's mass times gravitational acceleration. Further analysis is recommended, including drawing free body diagrams and writing equations of motion to clarify the tension dynamics. Understanding these concepts is crucial for solving rotational motion problems effectively.
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Homework Statement



I did a lab today where a weight was tied to a string. The string was wrapped around part of the circumference of a wheel, and then the end was taped down. So, when I let go of the wheel and the weight, the force of gravity on the weight causes the wheel to turn. I have two questions:

1. Is the angular momentum of the system made up of the wheel and the mass conserved?
2, Is the tension in the string constant?

Homework Equations



|Torque|=|F||r|sin(θ)
Angular momentum=I*\omega

The Attempt at a Solution



1. I think it isn't conserved because the force of gravity acting on the mass accelerates the system, making angular momentum not be conserved.
2. The tension is constant because it equals the mass of the weight times 9.8.
 
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You say "the end was taped down." Do you mean the end of the string was taped down? If so, how did this permit the system to move?

With regard to the tension in the string, draw some FBDs and write some equations of motion before you jump to a conclusion here.
 
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