Rigid body rotation. Need explanation

AI Thread Summary
The discussion focuses on understanding rigid body rotation and the relationship between linear and angular velocities using the equation V = rW. A participant attempts to solve a problem but arrives at an incorrect answer, leading to confusion about the correct relationship between the variables. They express uncertainty about their approach and seek clarification on the concept of angular momentum. Another user points out that angular velocity (W) differs in various scenarios, suggesting that this may be a key factor in resolving the confusion. The conversation emphasizes the importance of correctly applying the principles of rigid body dynamics to achieve accurate results.
am_knightmare
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Homework Statement



https://dl.dropbox.com/u/66988308/Capture.JPG

Homework Equations


V=rW

The Attempt at a Solution


I tried to plug in the forumla , and algebras but I keep getting rc/rf as answer instead of rf/rc as the book says.
Work:
Vf=(rf)W
W=Vf/rf
W=Vc/rc

Vc/rc = Vf/rf
(Vc)(rf) = (Vf) (rc)
(Vc)(rf) / (Vf) (rc)= 1
Im not sure if this is the right track.
Thanks for any advice.
 
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Please show your working.
 
The book is correct.
 
My work is shown in first post now.
 
"W" (ω), angular velocity, is not the same in each case.
 
Do you know what angular momentum is?
 
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