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Question
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?
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Solution
Given: Power, P = 100 W
Current, I = 3 A
Resistance, R = ?
We know, P = I2R
⇒ R = `P/I^2`
= `100/3^2`
= `100/9`
= 11.11 Ω
∴ The value of the resistance is 11.11 Ω.
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