Question

obtain the expression for the heat developed in a resistor by the passage of electric current through it m 220 J of heat is produced each second ina 8 ohm resistor . Find the potential difference across the resistor​

Answer 1

Heat = I^2 RT joules  

But V=IR (ohms law)

So I = V/R

Substituting I we get  

V^2/ R^2 × RT joules  

It gives V^2T/R joules

220 = V^2 × 1 sec/ 8 ohms now  

220 × 8 = v^2 and hence it comes to ~ 41.9