|J the derived SI unit of work or energy; the work done when the point of application of a force of 1 newton is displaced through a distance of 1 metre in the direction of the force. 1 joule is equivalent to 1 watt-second, 107 ergs, 0.2390 calories, or 0.738 foot-pound|
|[C19: named after James Prescott |
joule (jōōl, joul)
The International System unit of electrical, mechanical, and thermal energy.
A unit of electrical energy equal to the work done when a current of 1 ampere is passed through a resistance of 1 ohm for 1 second.
A unit of energy equal to the work done when a force of 1 newton acts through a distance of 1 meter.
|joule (jl, joul) Pronunciation Key
The SI derived unit used to measure energy or work. One joule is equal to the energy used to accelerate a body with a mass of one kilogram using one newton of force over a distance of one meter. One joule is also equivalent to one watt-second.
|Joule, James Prescott 1818-1889.
British physicist who demonstrated that heat is a form of energy. His work established the law of conservation of energy, stating that energy is never destroyed but may be converted from one form into another. The joule unit of energy is named for him.
unit of work or energy in the International System of Units (SI); it is equal to the work done by a force of one newton acting through one metre. Named in honour of the English physicist James Prescott Joule, it equals 107 ergs, or approximately 0.7377 foot-pounds. In electrical terms, the joule equals one watt-second-i.e., the energy released in one second by a current of one ampere through a resistance of one ohm.
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