Given,
emf of cell E = 200 V
Resistance = 1Ω
D. C. main supply voltage V = 220V
External resistance R = ?
r=(VE−V)R
1=(22020)×R
∴R=11Ω
JEE Main 2014 — Physics Electromagnetism
A d.c. main supply of e.m.f. 220V is connected across a storage battery of e.m.f. 200V through a resistance of 1Ω. The battery terminals are connected to external resistance R. The minimum value of R, so that a current passes through the battery to charge it is:
Held on 9 Apr 2014 · Verified 6 Jul 2026.
9Ω
7Ω
11Ω
0
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