In the diagram above, a bulb is lit by drawing 2.0A from 440V a.c. source. Calculate the cost of keeping the bulb on for two days at $0.40 per kilowatt-hour.

A. $16.90
B. $84.48
C. $1690.00
D. $8.48

Correct Answer:

Option A = $16.90

Explanation

Power [p] = IV → 2 * 440 = 880Watt

Energy = p * t = 880 * 48hrs

= 42240 or 42.24kwh

But 1 kwh cost $0.40
∴ 42.24kwh costs 42.24 x 0.40

= 16.896 or $16.90