# Frequency of an electric dipole

LittleLu609

## Homework Statement

Find the frequency of oscillation of an electric dipole, of dipole moment p and rotational inertia I, for small amplitudes of oscillation about its equilibrium position in a uniform electric field of magnitude E.

## Homework Equations

I think that the relevant equations are τ = I α , τ = pEsinθ , and α is the second derivative of θ

## The Attempt at a Solution

τ = I α
pEsinθ = I d2θ/dt2
Then I don't know where to go on from there. Am I even on the right track? Help?

Staff Emeritus
Homework Helper
Gold Member

## Homework Statement

Find the frequency of oscillation of an electric dipole, of dipole moment p and rotational inertia I, for small amplitudes of oscillation about its equilibrium position in a uniform electric field of magnitude E.

## Homework Equations

I think that the relevant equations are τ = I α , τ = pEsinθ , and α is the second derivative of θ

## The Attempt at a Solution

τ = I α
pEsinθ = I d2θ/dt2
Then I don't know where to go on from there. Am I even on the right track? Help?

For small values of θ, sin(θ) ≈ θ.

LittleLu609
For small values of θ, sin(θ) ≈ θ.

Oh, thanks! That's a big help! So from there, do I integrate the equation to solve for dθ/dt since dθ/dt = w? Then to find f I divide w by 2*pi?

EDIT: Nevermind, yay, I finally solved the problem! Thanks again for the help.

Last edited: