Question

If an appliance consumes 500 W of power and is left on for 5 hours, how much energy is used over this time period?

A. 2.5 kwh
B. 25 kwh
C. 250 kwh
D. 2500 kwh

Answer 1

A. 1000 watts is 1 kilowatt

Half of a kilowatt is 500 watts, or 0.5 of a kilowatt. 0.5 * 5 = 2.5

Or 500 watts * 5 hours (amount of time passing) = 2500

2500/1000 (or one kilowatt) = 2.5

2.5 kwh is the correct option

In summary, 1 kilowatt is 1000 watts

500 watts is half of a kilowatt

Every hour the appliance uses 500 watts or 0.5 (half) of a kilowatt