Using Gauss law for a cylindrical surface around the wire: E × 2πrl = λl/ε₀. So E = λ/(2πε₀r)
JEE Main 2023 — Physics Electromagnetism
The electric field at a distance r from an infinitely long uniformly charged wire having linear charge density λ is:
Verified 30 May 2026.
λ/(2πε₀r)
λ/(4πε₀r)
λ/(2πε₀r²)
λ/(4πε₀r²)
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