The SI unit of energy is the joule. Defined as: 1 joule is the work done by a force of 1 newton moving a distance of 1 metre in the direction of the force. It may also be defined in electrical terms as:the amount of energy needed to sustain 1 amp for 1 sec in a 1 ohm resistance.
Named after James Prescott Joule, one of the first to measure the “rate of exchange” between mechanical energy and heat.
Dimension: ML2T-2
1 J = 1 kgm2s-2
| 1 calorie | = | 4.1868 joules | 1 kilowatt hour | = | 3.6×106 J | |
| 1 therm (EEC) | = | 105.506×106 J | 1 therm (US) | = | 105.4804×106 J | |
| 1 thermie | = | 4.185407×106 J | 1 ft lb | = | 1.3558179 J | |
| 1 Btu | = | 1055 J | 1 electron volt | = | 1.602×10-19 J | |
| 1 joule | = | 107 ergs | 1 MMcfe | = | 1.091 terajoules |
Watt Hour: a unit of energy equivalent to one Watt of power expended for one hour of time. Abbreviated as Wh.
1 Wh = 3600 Joules