joule

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joule

(jo͞ol, joul), abbr. J, unit of workwork,
in physics and mechanics, transfer of energy by a force acting to displace a body. Work is equal to the product of the force and the distance through which it produces movement.
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 or energyenergy,
in physics, the ability or capacity to do work or to produce change. Forms of energy include heat, light, sound, electricity, and chemical energy. Energy and work are measured in the same units—foot-pounds, joules, ergs, or some other, depending on the system of
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 in the mks systemmks system,
system of units of measurement based on the metric system and having the meter of length, the kilogram of mass, and the second of time as its fundamental units. Other mks units include the newton of force, the joule of work or energy, and the watt of power.
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 of units, which is based on the metric systemmetric system,
system of weights and measures planned in France and adopted there in 1799; it has since been adopted by most of the technologically developed countries of the world.
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; it is the work done or energy expended by a force of 1 newton acting through a distance of 1 meter. The joule is named for James P. Joule.

joule

(jool) Symbol: J. The SI unit of energy, equal to the work done when the point of application of a force of one newton is moved one meter in the direction of the force.

Joule

 

a unit of energy and work in the International System of Units and the MKSA (meter-kilogram-second-ampere) system. It is equal to the work done by a force of 1 newton in moving a body 1 m in the direction of the force. It is named in honor of the English physicist J. Joule. In Russian the symbol is dzh; the international symbol is J.

At the Second World Conference of Electrical Engineers (1889) the joule was introduced into the absolute practical electrical units as the unit of work and energy for electric current. The joule was defined as the work done at a power of 1 watt in 1 second. The International Conference on Electrical Units and Standards (London, 1908) established “international” electrical units, among them the so-called international joule. After the return to absolute electrical units (beginning Jan. 1, 1948), the ratio of 1 international joule to 1.00020 absolute joules was adopted.

The joule is also used as a unit of quantity of heat. The ratio of the joule to other units is as follows: 1 joule = 107 ergs = 0.2388 calories.

G. D. BURDUN

joule

[jül or jau̇l]
(mechanics)
The unit of energy or work in the meter-kilogram-second system of units, equal to the work done by a force of 1 newton magnitude when the point at which the force is applied is displaced 1 meter in the direction of the force. Symbolized J. Also known as newton-meter of energy.

joule

A unit of energy or work; equals the work done by a force of 1 newton which acts over a distance of 1 metre in the direction of the force.

joule

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

Joule

James Prescott. 1818--89, English physicist, who evaluated the mechanical equivalent of heat and contributed to the study of heat and electricity

joule

A unit of energy in the MKS system. It is equal to 10,000,000 ergs in the CGS system. Surge protectors are often given joule ratings, but this refers only to the amount of energy they can absorb, not what gets through. See CGS system.
References in periodicals archive ?
The x-axis means S[N.sub.0] or S[N.sub.n] of HElib or SEAL libraries, and the y-axis means the total amount of energy consumption (in millijoules).
Assuming that clean glass has a surface free energy of several hundred millijoules per square meter, one would expect immediate wetting and submersion of glass fibers caused by a surfactant film of a surface free energy of approximately 25 mJ/[m.sup.2].
The 5 to 10 millijoules that expose a square centimeter of high- speed conventional plate surface is 20 to 40 times less energy than is needed to expose the same area on standard-speed plates, according to Antley.
The UVW employs low-pressure, germicidal ultraviolet (UV) light, delivering a dose of approximately 120 millijoules per square centimeter (mJ/[cm.sup.2]) under ideal water conditions at a flow rate of 4 gallons per minute (gpm).
For the Sarasota project, he and his colleagues first used a laser that put out 50 millijoules of energy per pulse, but found that it did not produce reliable plasma from wet or particularly dense wood.
The light energy, a maximum of 500 millijoules, delivered by the laser beam to the handpiece, is absorbed by the generally dark-colored stains on the stone being treated.
The buckyball solution, which at lower light levels transmits 80 percent of the energy, becomes more opaque when the laser's energy exceeds 240 millijoules per square centimeter ([cm.sup.2]).
Some authorities minimize the dangers of static electricity and other low-energy sparks because it takes a considerable amount of spark energy to initiate a dust deflagration--10 to 40 millijoules for a typical dust, versus 0.2 to 10 mJ for typical vapors.