Energy Transferred by Working
Energy and Thermal Physics


Physics Narrative for 11-14 Supporting Physics Teaching

Standard and not so standard units

The standard unit for energy is the joule, but not all energies are quoted in joules. There is therefore a very real chance that you will come across data in awkward units. If you need to perform conversions, the following tables should help.

Energy conversion table

energy unitequivalent
joule1 J
kilojoule1000 J
megajoule1 000 000 J
gigajoule1 000 000 000 J
terajoule1 000 000 000 000 J
Btu1055 J
therm105 500 000 J
gallon of petrol131 000 000 J
barrel of petrol5 498 000 000 J
barrel of crude oil6 119 000 000 J
ton of coal21 896 000 000 J
million cubic feet of natural gas1 083 000 000 000 J
calorie4.1868 J
kilocalorie4186.8 J
kilowatt-hour3 600 000 J

Power conversion table

1 Btu per hour0.293 W
1 joule per second1 W
1 kilowatt hour per day41.7 W
1 food calorie per minute69.77 W
1 horsepower745.7 W
1 kilowatt1000 W
1 Btu per second1054 W
1 gallon of gasoline per hour39 kW
1 million barrels of oil per day73 GW
Energy Transferred by Working
appears in the relation dU=dQ+dW
is used in analyses relating to Working Engines Thermionic Emission
is a special case of Work
has the special case Potential Energy Kinetic Energy
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