Question
Verify the energy unit equivalence that 1 kWh=3.60×106 J1\textrm{ kW}\cdot\textrm{h} = 3.60\times 10^{6}\textrm{ J}.
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OpenStax College Physics for AP® Courses, Chapter 20, Problem 48 (Problems & Exercises)

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Video Transcript
This is College Physics Answers with Shaun Dychko. We are going to convert 1 kilowatt-hour into joules and we will start by multiplying by 1000 watts for every kilowatt and then multiply by 1 joule per second for every watt because that's what watts mean— joules per second— and the watts cancel leaving us with joules per second now times hours and then multiply by 3600 seconds in every hour and these seconds will cancel with these seconds and we have 1 times 1000 times 3600 and joules are the units left over that is 3.60 times 10 to the 6 joules is equivalent to 1 kilowatt-hour. And the reason kilowatt-hours are used on utility bills is because they result in numbers that are easier to write down. It's unfamiliar for people to write things in scientific notation multiplied by 10 to some power but kilowatt-hours are easier... smaller numbers to work with.