A resistor carries a current of 3.0 A when connected across a potential difference of 24 V. What power is dissipated as heat?
Answer and explanation
Correct answer: C. 72 Watts
- Step 1: Electrical power is given by P = V * I.
- Step 2: P = 24 V * 3.0 A = 72 W.
Answer
72 Watts.
Why not the others: '8.0 Watts' divides voltage by current (V/I = R = 8 ohms); '216 Watts' computes VI3; '27 Watts' squares current and adds.
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