Engineering Board Exam Reviewer · Energy and Power · medium
A device uses 750 W for 2 hours. How much energy does it use?
- 1.5×103 J
- 5.4×106 J
- 2.7×106 J
- 5.4×103 J
Answer
B. 5.4×106 J
Solution
E=Pt=(750 W)(7200 s)=5.4×106 J (that is 1.5 kWh).
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