Q12 of 19 Page 60

Solve the example.

Heat energy is being produced in a resistance in a circuit at the rate of 100 W. The current of 3 A is flowing in the circuit. What must be the value of the resistance?

Answer: Given Power P = 100 W


Current I = 3 A


R =?


We know P = I2R;


where R is resistance


So R = P/ I2


⇒, R = = 11.11 ohm


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