Drift of electrons and electric currentइलेक्ट्रॉनों का अपवाह और विद्युत धाराDrift of electrons and electric current

NCERT Fig 3.3–3.4 · Class 12 Physics · Chapter 3 · interactive diagram

Parts and what they mean

• Conductor (metal wire) (चालक (धातु का तार)) — Has n free electrons per unit volume (about 10²⁹ m⁻³ for copper).
• Free electrons (मुक्त इलेक्ट्रॉन) — They move randomly at high thermal speeds and keep colliding with ions; without a field their average velocity is zero.
• Cross-section A (अनुप्रस्थ काट A) — Current = charge crossing this area per second.
• Drift velocity vd (अपवाह वेग vd) — A small average velocity (about 1 mm/s) superposed on the random motion, opposite to E: vd = −eEτ/m.
• Electric field E (विद्युत क्षेत्र E) — Set up inside the wire by the applied potential difference.
• Conventional current I (परंपरागत धारा I) — Along E, i.e. opposite to the electrons’ drift.

Original diagram drawn by Simple Learning Hub, based on NCERT Fig 3.3–3.4. Report a mistake