P = I^2 R = (0.04725)^2 * 5122 = 11.435W
11.435W * 1.2h = 13.722 W-hr = 0.013722 kW-hr
cost is thus 0.013722 kW-hr * 0.096¢/kW-hr = 0.001317¢
but I suspect that the power company charges $0.096 = 9.6 ¢/kW-hr, not 0.096¢/kW-hr ...
A 5122 Ω phone draws 47.25 mA from an outlet for 1.2 h. If the price of electricity is 0.096 cents/kWh, calculate the total cost of running the phone.
(if you could show steps/formulas used that'd be great :))
1 answer