Frequency of an electric dipole

AI Thread Summary
The discussion focuses on calculating the frequency of oscillation for an electric dipole in a uniform electric field. The relevant equations include torque (τ = I α) and the relationship between torque and dipole moment (τ = pE sinθ). The user initially struggles with the next steps after establishing the equations but receives guidance on approximating sin(θ) for small angles. They confirm that integrating the equation leads to the angular frequency (ω), which can be divided by 2π to find the frequency (f). Ultimately, the user successfully solves the problem with assistance from others.
LittleLu609
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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.

Answer: [(pE/I)^0.5]/(2*pi)


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?
 
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LittleLu609 said:

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.

Answer: [(pE/I)^0.5]/(2*pi)


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.
 
SammyS said:
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.
 
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