Question

standard electricity consumption
you have a homeowner who is excited by their new plasma tv they were given after an earthquake. in one day, the homeowner watched 8 hours of tv.
how much did it cost in electricity to watch hours of television?
(include the electricity for the cable box.)
22 cents
3 cents
25 cents

• the wattage for the plasma television is 0.25 kw
• the wattage for the cable box is.008kw
• the average cost per kwh is $0.12

Explanation:

Step1: Calculate total power consumption

First, find the total power of the TV and cable box. The power of the TV is \(P_{TV}=0.25\space kW\) and the power of the cable box is \(P_{box}=0.008\space kW\). So the total power \(P = P_{TV}+P_{box}=0.25 + 0.008=0.258\space kW\).

Step2: Calculate energy consumption

Use the formula \(E=P\times t\), where \(t = 8\space h\). Then \(E=0.258\times8 = 2.064\space kWh\).

Step3: Calculate cost

Use the formula \(C = E\times\) cost per \(kWh\). Given the cost per \(kWh\) is \(\$0.12\). So \(C=2.064\times0.12=\$0.24768\approx25\) cents.

Answer:

25 cents