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Cell having an emf ε and internal resistance r is connected across a variable external resistance R. As the resistance R is increased, the plot of potential difference V across R is given by :
Correct Option: C
The current through the resistance R
| I = |  |  | R | |||
| ε | R + r |
The potential difference across R
| V = IR = | | | R | |||
| ε | R + r |
when R = 0, V = 0,
R = ∞, V = ε Thus V increases as R increases upto certain limit, but it does not increase further.
