Science 9 help- Electricity question, please help?

Question

A. An electronic clothes dryer runs on 240 V and 24 A and is used for 45 minutes (0.75 hours) on its longest drying cycle. How much energy does it consume in that time:

I. In joules?

II. In kW.h?

B. What would it cost to operate the dryer if the power were prices at 6 cents for every kilowatt-hour?

Answer 1

a) 240v x 24a = 5760 watts

5760 watts x 3/4 hour = 4320 watt hours, or 4.32 kW-hr

5760 watts x 45 min x 60sec/min = 15550000 Jouiles

b)4.32 kW-hr x .06 = $0.26