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CFL and LED

APES-ERGLY3

Energy flow can be described by the term power. In the U.S., we measure electricity in kWh.

Compare the amount of electricity used over the course of a year by a compact fluorescent light bulb (CFL) and a light-emitting diode bulb (LED) if both are used 8 hours a day, the CFL uses 14 watts, and the LED uses 10 watts.

Hint: remember to convert to kilowatts first.

A

CFL = 40,880 kWh

LED = 29,200 kWh

B

CFL = 0.112 kWh

LED = 0.08 kWh

C

CFL = 0.014 kWh

LED =0.010 kWh

D

CFL = 40.9 kWh

LED = 29.2 kWh

E

CFL = 30 kWh

LED = 10 kWh