Two point charges −q and +q are placed at a distance L, as shown in the figure. The magnitude of electric field intensity at a distance R (R ≫ L) varies as: [Diagram: Image]
Physics · Electrostatic · Electric Dipole & Dipole Moment
NEET 2022 NEET Previous Year

Question

Two point charges −q and +q are placed at a distance L, as shown in the figure. The magnitude of electric field intensity at a distance R (R ≫ L) varies as: [Diagram: Image]

G1 Physics · Accepted Answer

Step 1: Two equal opposite charges separated by L form an electric dipole with moment p = qL. Step 2: At large distance R ≫ L, the leading dipole electric field scales as p/(4πε₀R³). Step 3: Hence E ∝ R⁻³.