Question

If the voltage across a circuit of constant resistance is doubled, how is the current in the circuit affected?
(a)-The current is quadrupled.
(b)-The current is reduced by a factor of 2.
(c)-The current is reduced by a factor of 4.
(d)-The current remains constant.
(e)-The current is doubled.

Answer 1

Answer:

(e)-The current is doubled.

Explanation:

According to Ohm law, $I = \frac{V}{R}$ where I is the current, V is the voltage and R is the resistant.

$I_1 = \frac{V_1}{R_1}$

$I_2 = \frac{V_2}{R_2}$

If V is doubled, $V_2 = 2V_1$ while R remains constant $R_2 = R_1$ we would have

$I_2 = \frac{2V_1}{R_1} = 2(\frac{V_1}{R_1}) = 2I_1$

The current is doubled.