SI unit of energy, work, and heat
1 joule = 1 newton times 1 meter = 1 kg-m2/s2
named after James Prescott Joule, who established the mechanical equivalent of heat
1 calorie = 4.184 joules; food energy commonly expressed in kilocalories (kcal)
1 watt = 1 joule per second
electron-volt (eV) = 1.602e-19 joules, used in particle physics
kilowatt-hour (kWh) = 3.6 million joules, the standard billing unit for electricity
connects force, distance, power, and temperature through the first law of thermodynamics