Electric field of a dipole: axial and equatorial pointsद्विध्रुव का विद्युत क्षेत्र: अक्षीय और विषुवतीय बिंदुElectric field of a dipole: axial and equatorial points
NCERT Fig 1.17 · Class 12 Physics · Chapter 1 · interactive diagram
Parts and what they mean
- Charge −q (आवेश −q) — One end of the dipole.
- Charge +q (आवेश +q) — Other end of the dipole.
- Separation 2a (दूरी 2a) — Distance between the two charges.
- Centre O of the dipole (द्विध्रुव का केंद्र O) — Distances r of P and Q are measured from here.
- Dipole moment p = q × 2a (द्विध्रुव आघूर्ण p = q × 2a) — A vector pointing from −q to +q along the axis. SI unit: C m.
- Point P on the axis (अक्ष पर बिंदु P) — E = 2pr/[4πε₀(r² − a²)²] ≈ 2p/(4πε₀r³) for r ≫ a, along p.
- Field at P due to +q (P पर +q के कारण क्षेत्र) — Points away from +q; larger, because +q is nearer to P.
- Field at P due to −q (P पर −q के कारण क्षेत्र) — Points towards −q; smaller. The two do not cancel, so net E is along p.
- Point Q on the equatorial line (विषुवतीय रेखा पर बिंदु Q) — E = p/[4πε₀(r² + a²)^(3/2)] ≈ p/(4πε₀r³) for r ≫ a, opposite to p.
- Field at Q due to +q (Q पर +q के कारण क्षेत्र) — Same size as the field due to −q (equal distances).
- Field at Q due to −q (Q पर −q के कारण क्षेत्र) — Its component along the equatorial line cancels that of E₊q.
- Net field at Q (Q पर परिणामी क्षेत्र) — Parallel to the axis but opposite to p (from +q towards −q).
Original diagram drawn by Simple Learning Hub, based on NCERT Fig 1.17. Report a mistake