Pendulum - equipartition experiment

AI Thread Summary
The discussion revolves around a homework problem related to the equipartition theorem and its application to a pendulum-like system. The user explains their understanding of energy conservation, equating kinetic and potential energy in the context of oscillation. They express confusion regarding degrees of freedom in relation to the equipartition theorem, questioning whether to count rotational movements as separate degrees of freedom. The user concludes that for part b, the total energy contribution should be KbT, acknowledging the squared terms in the energy expressions. They seek further assistance on part c, specifically how to express the answer in radians or degrees without using trigonometric functions.
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Homework Statement



The problem is : http://i44.tinypic.com/2v7yo29.png

Homework Equations


The Attempt at a Solution


For part a )
I have stated that: The total energy is equivalent to the conservation of energy i.e the two expressions obey the conservation principle. The expression dealing with inertia is the kinetic energy while the other expression's potential since this experiment can be analogous to a pendulum's oscillation.

b)
Now I know that equipartitions states that in thermal equlibirum each degrees of freedom contributes 1/2Kbt i.e for every squared term for the expression of the energy.
In the above case we have two squared expressions.. however i am a little confused with the degrees of freedom. The general mean equation is :
f/2 k_{b}T ...<br /> <br /> Would the mean total be 2/2 kbt since each expression gives one degrees of freedom.. Or I was thinking that since the glass can rotate in both direction ( clockwise and vice versa) so would that be 2 degrees of freedom for kinetic energy and 2 for potential as well ? :s <br /> <br /> These are the only bits I am stuck on. Thanks for your expected replies!<br /> <br /> EDIT: I think for part b the answer is simply Kbt since each squared independent variable provides 1/2 Kt according to the theorem. :yea =)
 
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I am little stuck on part c... how can I get answer in radians or degrees.. if i don't have any trig. function ?
 
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Anyone ?
 
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