
vnet=5(Rkq)+(R5k(−q))
vnet=0,[Qnet=0]
Enet=0, by symmetry
JEE Main 2020 — Physics Electromagnetism
Ten charges are placed on the circumference of a circle of radius R with constant angular separation between successive charges. Alternate charges1,3,5,7,9 have charge (+q) each, while 2,4,6,8,10 have charge (–q) each. The potential V and the electric field E at the centre of the circle are respectively : (TakeV=0 at infinity)
Held on 5 Sept 2020 · Verified 6 Jul 2026.
V=4πϵ0R10q;E=0
V=0,E=4πϵ0R210q
V=0;E=0
V=4πϵ0R10q;E=4πϵ0R210q
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