A machine does 1200 J of work in 10 s. What is its power?
Answer and explanation
Correct answer: C. 120 W
- Step 1: Power = work ÷ time. Step 2. P = 1200 ÷ 10 = 120 W. Answer: 120 W. Why not the others: 12000 W is what you get if you multiply instead of divide. 0.008 W is what you get if you invert the ratio. 1190 W is what you get if you subtract the numbers.
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