if you have 2 point dipoles(adsbygoogle = window.adsbygoogle || []).push({}); p1 andp2 located atr1 andr2 respectively(all four are vectors)

what's the energy ofp2 in the field ofp1?

I know the general expression for the energy of a dipole in an external fieldEo is U=-p * Eo but from there I get confused

I can express the electric field of the dipole in terms of its radial and angular components, but I'm not sure how to expressp2 in those same terms.

FYI the answer is Udd=1/(4pi*epsilon*R^3)*[p1*p2 - 3(p1*R)(p2*R)]

both those bold Rs are unit vectors, * is dot product if it's between two vectors

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Derivation of dipole-dipole interaction energy

**Physics Forums | Science Articles, Homework Help, Discussion**