A 6 Ω resistor is connected across a 12 V supply. What power is dissipated?
Answer and explanation
Correct answer: C. 24 W
- Step 1: P = V² ÷ R.
- Step 2: 12² ÷ 6 = 144 ÷ 6 = 24 W.
Answer
24 W.
Why not the others: 72 W: the voltage and resistance were multiplied. 2 W: this is the current in amperes. 0.5 W: the formula was inverted.
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