What would be the energy usage in kilowatt-hours of an appliance consuming 100 watts over a period of 10 hours?

To determine the energy usage of an appliance consuming 100 watts over a period of 10 hours, you can apply the formula for calculating energy consumption, which is:

Energy (in kilowatt-hours) = Power (in kilowatts) × Time (in hours).

First, convert the power from watts to kilowatts. Since 1 kilowatt is equal to 1,000 watts, you can express 100 watts as 0.1 kilowatts.

Now, substituting the values into the equation gives:

Energy = 0.1 kW × 10 hours = 1 kWh.

This calculation shows that an appliance with a power rating of 100 watts operating for 10 hours will use 1 kilowatt-hour of energy. This is the correct answer, and it aligns with the fundamental principles of electricity consumption. Understanding this principle is crucial for students in power engineering, as it allows for the assessment of energy costs and efficiency in electrical systems.