alleryStart learning →Household electricity is sold in units of one kilowatt hour. What does one kilowatt hour mean?
AOne kilowatt for one day
BOne joule for one hour
COne kilowatt for one hour
DOne watt for one hour
Answer & Solution
Correct answer: C. One kilowatt for one hour
1. A kilowatt hour is a unit of energy, not a unit of power.
2. One kilowatt hour refers to the use of one kilowatt of power for one hour.
3. Knowing the power rating of an appliance therefore lets you work out what it costs to run.
4. A watt is a thousand times smaller than a kilowatt, so the last option names a much smaller amount of energy.
_Source: Siyavula Physical Sciences Grade 11 (Everything Science, CC BY 4.0), Chapter 11: Electric circuits_
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