When you pay the electric company by the kilowatt-hour, what physical quantity are you actually paying for?
voltage
energy
current
power
none of the above
2007-09-23 13:17:51 · 4 answers · asked by WMC 1 in Science & Mathematics ➔ Physics
Power and current are wrong answers, so the answer is one of three remaining. Please help! Thanks!
2007-09-23 13:25:10 · update #1
A kilowatt*hr is a unit of energy
A watt is a unit of power, or energy divided by time
a kilowatt is 1000 watts
(a watt is one Joule per second)
an hour is a unit of time, so a kilowatt hour is a unit of energy.
j
2007-09-23 13:23:36 · answer #1 · answered by odu83 7 · 2⤊ 0⤋
Well, kilowatt hour is not kilowatts per hour, but rather kilowatts * hours. Like you said, a Watt is just 1 Joule / second, so a kilowatt is simply 1000 Joules / second. Now, an hour is just 3600 seconds, so a kilowatt hour is 1000 (Joules/second) * 3600 (seconds) = 3,600,000 Joules which I guess is a convenient unit of measuring energy (since Joules are units of energy) for the electric company to keep track of how much you are using. So the answer is (B), Energy.
2016-05-17 06:49:16 · answer #2 · answered by ? 3 · 0⤊ 0⤋
None of the above, you pay for kilowatt hours.
2007-09-27 09:35:28 · answer #3 · answered by johnandeileen2000 7 · 0⤊ 0⤋
watts is a unit of power
2007-09-23 13:22:00 · answer #4 · answered by Anonymous · 0⤊ 0⤋