A 25 ohm heater carries a current of 3 A. What power does it dissipate?
Answer and explanation
Correct answer: B. 225 W
- Step 1: Power dissipated in a resistor is P = I^2 R.
- Step 2: P = 3^2 x 25 = 225 W.
Answer
225 W.
Why not the others: The current must be squared; I x R is a voltage, and the other values double or halve the result.
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