Angular momentum/ energy conservation.

AI Thread Summary
The discussion revolves around a physics problem involving a block suspended by a string and a pulley, focusing on energy conservation and angular momentum. The user attempts to apply the energy conservation equation but is unsure why their calculations do not yield correct results. They express confusion about the energy loss term in their equation. Other participants encourage the user to provide numerical figures to clarify the issue. The conversation highlights the importance of correctly applying energy conservation principles in mechanics problems.
Roland of G
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Homework Statement


A block of mass 7.00×10-1kg is suspended by a string which is wrapped so that it is at a radius of 6.00×10-2m from the center of a pulley. The moment of inertia of the pulley is 5.70×10-3kg*m2. There is friction as the pulley turns. The block starts from rest, and its speed after it has traveled downwards a distance of D=0.790m is 1.233m/s. Calculate the amount of energy dissipated up to that point.
I set up an equation like this:
mgh=1/2mv^2+mg(h final)+1/2iw^2+L(energy loss) This makes sense to me... Why does this not work correctly?


Homework Equations





The Attempt at a Solution


mgh=1/2mv^2+mg(h final)+1/2iw^2+L(energy loss) This makes sense to me... Why does this not work correctly?
 
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Welcome to PF!

Hi Roland of G! Welcome to PF! :smile:

(have an omega: ω and try using the X2 icon just above the Reply box :wink:)
Roland of G said:
mgh=1/2mv^2+mg(h final)+1/2iw^2+L(energy loss) This makes sense to me... Why does this not work correctly?

It should work. :confused:

Show us the figures. :smile:
 
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