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

Explanation

We are given, potential difference V = 60 V, current I = 4 A.
According to Ohm’s law, `R=V/I = ( 60 V )/( 4A) = 15 Omega `
When the potential difference is increased to 120 V the current is given by
current =`(V) /(R) =(120 V )/(15 ) = 8A `
The current through the heater becomes 8 A.