
Electric field due to a long cylinder is,
E=2πϵ0rλ=2πϵ0rρA
If a charge q is rotating in a circle of radius r
rmv2=qE ⇒rmv2=q2πϵ0rρA⇒21mv2=4πϵ0qρπR2=4ϵ0qρR2
JEE Main 2022 — Physics Electromagnetism
A long cylindrical volume contains a uniformly distributed charge of density ρ. The radius of cylindrical volume is R. A charge particle (q) revolves around the cylinder in a circular path. The kinetic energy of the particle is :
Held on 24 Jun 2022 · Verified 6 Jul 2026.
4ϵoρqR2
2ϵoρqR2
4ϵ0R2qρ
qρ4ϵ0R2
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