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When a resistance of 2 ohm is connected ...

When a resistance of 2 ohm is connected across terminals of a cell, the current is `0.5 A`. When the resistance is increased to 5 ohm, the current is `0.25 A` The e.m.f. of the cell is

A

0.5 ohm

B

1.0 ohm

C

1.5 ohm

D

2.0 ohm

Text Solution

Verified by Experts

The correct Answer is:
B
`0.5(r + 2) = 0.25 (5 + r)`
`rArr 2r + 4 = 5 + r rArr r = 1 Omega`
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