Electrostatic class 11 || Couple Acting on an Electric Dipole in a Uniform Electric Field || part 08

📘 *Topic: 10.9.1 Couple Acting on an Electric Dipole in a Uniform Electric Field – Class 11 Electrostatics* 🔹 *Concept:* When an *electric dipole* is placed in a *uniform electric field (E)**, it experiences **equal and opposite forces* on its two charges (+q and –q). These forces form a *couple* and produce a **torque**. --- 🔹 *Dipole Setup:* Two charges: +q and –q Separated by distance: *2l* Dipole moment: *p = q × 2l* Placed in uniform electric field *E* Dipole makes angle *θ* with the field --- 🔹 *Forces on the Charges:* Force on +q = *+qE* (along the field) Force on –q = *–qE* (opposite to the field) These two forces are *equal in magnitude* and **opposite in direction**, but act at different points → Hence, form a **couple**. --- 🔹 *Torque on Electric Dipole (τ):* 🧮 *Formula:*     *τ = pE sinθ* Where: *τ* = Torque *p* = Dipole moment *E* = Magnitude of Electric Field *θ* = Angle between *p* and *E* 👉 *Direction of Torque:* Tends to align dipole along the electric field direction. --- 🔹 *Special Cases:* 1️⃣ When *θ = 0° or 180°* → sinθ = 0 ⇒ τ = 0  (Dipole aligned with field → No rotation) 2️⃣ When *θ = 90°* → sinθ = 1 ⇒ τ = maximum  (Dipole is perpendicular to field → Maximum torque) --- ✅ *Conclusion:* Dipole in uniform electric field does not experience a net force. It experiences a torque which tends to *align* the dipole with the field. --- 📌 Class 11 | Chapter: Electrostatics | Part-08 📌 100% Concept Clear | With Proof and Diagram 📌 Important for Board + Competitive Exams --- 🔖 *Hashtags:* #ElectricDipole #TorqueOnDipole #UniformElectricField #Class11Physics #Electrostatics #DipoleMoment #PhysicsDerivation #ConceptClear #PhysicsWithDiagram #Std11Physics #CoupleOnDipole #DipoleInField