In your four years at college you dry your hair every day for 5 minutes with a 1200-W hair dryer. If the average price of electrical energy was $0.085 per kilowatt-hour, how much did it cost you during this time? Assume 1 year = 365 days.)

Question

Quizplus · Accepted Answer

Power consumed by the hair dryer = 1200 W
Time taken to dry hair per day = 5 minutes = 0.083 hours
Energy consumed per day = Power x Time taken = 1200 x 0.083 = 99.6 Wh = 0.0996 kWh
Total energy consumed in 4 years = 0.0996 x 365 x 4 = 144.936 kWh
Cost of electrical energy per kWh = $0.085
Total cost = 144.936 x $0.085 = $12.34, which is closest to option C, $12.40.

In Your Four Years at College You Dry Your Hair