How much energy was consumed in this billing cycle, in Joules, using the picture of the billing cycle below.?

Question

Billing cycle picture: http://i28.tinypic.com/xblfuo.jpg

a. How much energy was consumed in this billing cycle, in joules?

b. What is the average energy consumed per day in kilowatt-hours, in units of kWh/day?

c. What is the average energy consumed per day in Joules, in J/day?

d. If the cost of energy was increased to $0.38/kWh, how much more would energy cost in this billing cycle? Fuel remains constant.

Thanks!

Answer 1

This is fairly straightforward.

1 kWh = 3.6x10^6 J

503 kWh = 1.81x10^9 J

503 kWh/60 days = 8.38kWh/day

1.81x10^9 J / 60 days = 3.02x10^7 J/day

Energy cost = $0.38 / $0.0355 =  10.7 times more expensive, so $17.86 x 10.7 = $191.10

Answer 2

1.  Multiply the number of kilowatt-hours by 3,600,000.

2.  Divide the number of kilowatt-hours by the number of days in the billing period.

3.  Divide the number of joules calculated in step (1) by the number of days.

4.  Multiply the number of kWh by 0.038.