Chapter 1: Q8DQ (page 228)

Fractured Physics. People often call their electric bill a power bill, yet the quantity on which the bill is based is expressed in kilowatt-hours. What are people really being billed for?

Short Answer

Expert verified

The people are really paid for the electric bill.

Step by step solution

Concept/Significance of power

The power is generally expressed in or more commonly as watts. The power is the change in work over a given time interval.

$P = \underset{∆ t \to 0}{l i m} \frac{∆ W}{∆ t} = \frac{d W}{d t}$

Find what people are being billed for

The electricity bill is calculated with and this is the unit of energy. A kilowatt-hour is equal to the energy provided by $1000 watts$ in one hour.

$1 kWh = 1 (10^{3} W) (hour) = 10^{3} (\frac{J}{s}) (3600 s) = 3.6 \times 10^{6} J$

The electricity bill is prepared based on the number of kilowatt-hours consumed. Kilowatt-hour is a unit of electrical energy which means the electricity bill is prepared on the consumption of electrical energy. Therefore, the bill is really called an electric bill rather than a power bill.

Hence, the people are paid for the electric bill.