Show Energy Equality of Simple Pendulum with Equipartition

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Glenda
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Homework Statement


How would one show that the average total energy of a simple pendulum is equal to twice the average kinetic energy of the pendulum?

Homework Equations


E = T + V = 1/2 ml**2 (θ'**2) + mgl cos(θ)



The Attempt at a Solution


Maybe use equipartition?
 
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Glenda said:
Maybe use equipartition?
Then you have to show that your pendulum satisfies the assumptions going into that theorem. In particular, your pendulum is not in thermal equilibrium with anything, and a different potential shape will lead to a different result so it does not apply to all pendulum-like systems.

You can explicitly calculate the average kinetic energy by integrating over one period.