Energy
Convert between different units of energy used in physics, engineering, nutrition, and everyday applications
Energy Converter
Convert between different units of energy used in physics, engineering, nutrition, and everyday applications
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About Energy
Explore energy units from various scientific and engineering disciplines, from everyday measurements to specialized applications
Historical Context
Energy units have evolved across different fields of science and engineering. The joule, named after English physicist James Prescott Joule, became the standard SI unit in the late 19th century. Different disciplines developed their own units: electrical engineers use kilowatt-hours, nutritionists use calories, mechanical engineers use foot-pounds, and nuclear physicists use electron-volts.
Modern Standards
Today, the joule (J) is the standard SI unit for energy, defined as the energy transferred when applying a force of one newton through a distance of one meter. While the joule is the scientific standard, specialized fields continue to use their traditional units: kilowatt-hours for electricity billing, BTUs for heating and cooling, calories for food energy, and electron-volts for atomic physics.
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Conversion Reference
Quick reference for common energy conversions