Q20 of 330 Page 66

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

Here, it is given H = 100J, t = 1sec, R = 4ohms,

We know that according to Joule's law of heating


H = I2RT


100 = I2×4×1


100/4 = I2


I = 5amp


Again we know that


V = IR


V = 5X4


= 20V


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