Which of the following is equivalent to one kilowatt hour?

One kilowatt hour (kWh) is a unit of energy that represents the amount of energy consumed when a power of one kilowatt (1,000 watts) is used for one hour. Therefore, the expression "1,000 watts for one hour" accurately defines this measurement.

To elaborate, the term "kilowatt" is a measure of power (1 kW = 1,000 watts), and the "hour" is a measure of time. When these two are combined, they represent energy consumed over that period. Specifically, if you run an appliance that uses 1,000 watts for one hour, it would consume 1 kilowatt hour of energy.

The other options presented do not correctly reflect the definition of one kilowatt hour. For instance, using 1,000 watts for one day factors in a much longer time period, leading to higher energy consumption, and using 10,000 watts for one hour represents a much greater amount of energy. Similarly, 100 watts for ten hours yields only one kilowatt hour but is not the direct expression of one kilowatt hour itself. Thus, understanding how power and time interact is essential for mastering these concepts in utility services.