Question

100 joules of heat is produced per second in a 4 ohm resistor. What is the potential difference across the resistor ?

Answer 1

Given H = 100J,t = 1 sec, R = 4 ohms,

We know that

H = I²RT

100 = I² x 4 x 1

100/4 = I²

I = 5 amp

V = IRa

V = 5 x 4

= 20 V