Question

Keeping the p.d. constant, the resistance of the circuit is halved. The current will become.
(a) One-fourth (b) four times (c) half (d) double

Answer 1

From Ohm's law, $I=\frac{V}{R}$

When resistance is halved, $I^{\prime }=\frac{V}{R^{\prime }}=\frac{V}{\frac{R}{2}}=2\frac{V}{R}=2I$

Hence, the current doubles and the correct choice is (d).