🧭 Dipole in a Uniform Field

📖 The Physics

An electric dipole is just two equal and opposite charges held a small distance apart. Its dipole moment p = q·2a points from the −q charge to the +q charge.

In a uniform field the two charges feel equal but opposite forces — so there is no net push, but there is a couple (a pair of forces) that twists the dipole until it lines up with the field.

Press Release and watch it swing into line like a compass needle. Torque is largest at θ = 90° and zero when aligned (θ = 0°, lowest energy) or exactly opposed (θ = 180°, unstable). This is why polar molecules turn in a field.