Question

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.​

Answer 1

Given:-

Original potential difference, v = 60V

original current drawn,i = 4A

Required Answer:-

Current drawn when potential difference is 120V.

Answer:-

We have,

v = 60V

and, i = 4A

Using Ohm's law,

V = IR

R = V/I

therefore,

R = 60/4 = 15 ohm

Now, new p.d. V = 120 V

and R = 15 ohm

therefore, current, I = 120/15 = 8 A

Hence, the current drawn will be 8 A.