Physics C mech 2004 FR (2) - Pulley and Rotational Inertia

AI Thread Summary
The discussion centers on a problem from the 2004 AP Physics C Mechanics exam regarding the change in rotational inertia in a pulley system. A participant expresses confusion about why the rotational inertia would vary and seeks clarification on the layout changes of the disk and pulley. It is suggested that data interpolation might have contributed to errors in estimating inertia. Another contributor points out that the discrepancy arises from the effects of the string, which are often overlooked in simplified models. Understanding these real-world factors is crucial for accurately solving the problem.
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Homework Statement



http://apcentral.collegeboard.com/apc/public/repository/ap04_frq_physics_cm_36191.pdf
The problem can be found here. I am stuck on problem 2 d.

Homework Equations


I = m(g-a)R2 / a //found in part c


The Attempt at a Solution


I don't understand why the Rotational Inertia would change. Can someone describe to me the change in the layout of the disk and pulley too?
 
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One possible answer could be that the data interpolation led to a certain error in the estimation of inertia.

Other reasons I can't really imagine.
 
data interpolatin? What's that?

bump
 

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