Electric Charges & Fields
Class 12 · Electric Charges & Fields
Torque on Dipole
τ = pE sinθ. Drag dipole to rotate, watch torque arrow flip.
Key Notes
01
Uniform field exerts no net force on a dipole, but creates torque τ⃗ = p⃗ × E⃗.
02
|τ| = pE sinθ where θ = angle between p⃗ and E⃗.
03
Torque tries to align p⃗ with E⃗ (stable equilibrium at θ = 0°).
Formulas
Torque
|τ| = pE sinθ.
Potential energy
Min at θ = 0°, max at θ = 180°.
Important Points
Stable equilibrium: p∥E (θ=0). Unstable: p anti-parallel (θ=180°).
Work done rotating from θ₁ to θ₂: W = pE(cosθ₁ − cosθ₂).
Torque on Dipole notes from sciphylab (also known as SciPhy, SciPhy Lab, SciPhy Labs, Physics Lab). Class 12 physics revision for JEE Mains, JEE Advanced, NEET UG, AP Physics 1/2/C, SAT, and CUET-UG.