A small ball of mass M carries a positive charge Q. The ball is glued to the end of a massless stick of length L. The other end of the stick is attached to a frictionless pivot that allows the pendulum to swing in the xy plane. Gravity is in the minus y direction. A constant electric field Eº points in the positive x direction.(adsbygoogle = window.adsbygoogle || []).push({});

1) Find a potential energy as a function of angle θ and find an expression for the equilibrium angle(s). How many are there? Explain

2) Find the angular frequency, ωo, of small oscillations about the stable equilibrium angle, θs.

3) Assume that the pendulum is ocsillating with aplitude θo-θs. Find the work done by the electric field as the pendulum moves from θs-θo to θs+θo.

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# Homework Help: Mechanics potential energy problem

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