Question

The potential difference between the terminals of an electric heater is $60V$ when it draws a current of $4A$ from the source. What current will the heater draw if the potential difference is increased to $120V$?

Answer 1

$V=60VI=4A$

$R=\frac{V}{I}=\frac{60}{4}=15\Omega$

When potential difference is increased to 120V

$I=\frac{V}{R}=\frac{120}{15}=8A$

The current through the heater becomes 8A