Field of an infinitely long charged wire (Gauss’s law)अनंत लंबे आवेशित तार का क्षेत्र (गाउस नियम)Field of an infinitely long charged wire (Gauss’s law)

NCERT Fig 1.26 · Class 12 Physics · Chapter 1 · interactive diagram

Parts and what they mean

• Infinitely long thin wire, charge λ per metre (अनंत लंबा पतला तार, प्रति मीटर आवेश λ) — Uniform linear charge density λ (C m⁻¹).
• Field E: radial, away from the wire (क्षेत्र E: त्रिज्य, तार से दूर) — By symmetry E is perpendicular to the wire and has the same size at the same distance r.
• Gaussian surface: coaxial cylinder (गाउसीय पृष्ठ: समाक्ष बेलन) — Flux through the curved part = E × 2πrl. Charge enclosed = λl. So E × 2πrl = λl/ε₀.
• Flat circular ends (चपटे वृत्ताकार सिरे) — E lies along these faces (perpendicular to their normal), so they carry no flux.
• Radius r (त्रिज्या r) — Perpendicular distance of the point from the wire.
• Length l of the cylinder (बेलन की लंबाई l) — Any length; it cancels out: E = λ/(2πε₀r).

Original diagram drawn by Simple Learning Hub, based on NCERT Fig 1.26. Report a mistake