A machine does 600 J of work in 20 s. What is its power?
Answer and explanation
Correct answer: A. 30 W
- Step 1: Power = work ÷ time. Step 2. P = 600 ÷ 20 = 30 W. Answer: 30 W. Why not the others: 12000 W is what you get if you multiply instead of divide. 0.033 W is what you get if you invert the ratio. 580 W is what you get if you subtract the numbers.
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