Practice portal › Electric Charge and Properties › Electric Dipole
Asked in GSEB Board August 2020 · Torque, energy and work done
Idea: the potential energy of a dipole in a uniform field is U=-⃗p·⃗E=-pE cos θ.
U is smallest when cos θ is largest, that is cos θ=1.
That gives θ=0°: the dipole aligned with the field, with Uₘᵢₙ=-pE.
This is the position of stable equilibrium - turn the dipole slightly and the torque turns it back.
Reading this solution needs no sign-in. You only sign in to practise against the clock and keep your progress.
Practise this with a timer