A lightbulb has a power of 100 W. and is used for 4 hours. A microwave has a power of 1200 W and is used for 5 minutes.

a. How much energy is used by the lightbulb?

b. How much energy is used by the microwave?

c. The lightbulb has an efficiency of 1.8%. How much heat energy does the lightbulb produce in 4 hours?

Question

25 September, 06:01

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Answers (1)

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Darnell Mays · Answer 1

a) E=Nt=100 * (4*3600) = 1440000 J

b) E=1200 * (5*60) = 360000 J

c) Q=E * (100-1.8) / 100=1414080 J