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Energy, United States Department of

(Encyclopedia)Energy, United States Department of, executive department of the federal government responsible for coordinating national activities relating to the production, regulation, marketing, and conservation...

United Nations Atomic Energy Commission

(Encyclopedia)United Nations Atomic Energy Commission: see disarmament, nuclear. ...

potential, electric

(Encyclopedia)potential, electric, work per unit of electric charge expended in moving a charged body from a reference point to any given point in an electric field (see electrostatics). The potential at the refere...

work

(Encyclopedia)work, 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. Although both fo...

photoelectric effect

(Encyclopedia)photoelectric effect, emission of electrons by substances, especially metals, when light falls on their surfaces. The effect was discovered by H. R. Hertz in 1887. The failure of the classical theory ...

phosphorescence

(Encyclopedia)phosphorescence fŏsˌfərĕsˈəns [key], luminescence produced by certain substances after absorbing radiant energy or other types of energy. Phosphorescence is distinguished from fluorescence in th...

momentum

(Encyclopedia)momentum mōmĕnˈtəm [key], in mechanics, the quantity of motion of a body, specifically the product of the mass of the body and its velocity. Momentum is a vector quantity; i.e., it has both a magn...

electron-volt

(Encyclopedia)electron-volt, abbr. eV, unit of energy used in atomic and nuclear physics; 1 electron-volt is the energy transferred in moving a unit charge, positive or negative and equal to that charge on the elec...

kinetic art

(Encyclopedia)kinetic art, term referring to sculptured works that include motion as a significant dimension. The form was pioneered by Marcel Duchamp, Naum Gabo, and Alexander Calder. Kinetic art is either nonmech...

thermodynamics

(Encyclopedia)thermodynamics, branch of science concerned with the nature of heat and its conversion to mechanical, electric, and chemical energy. Historically, it grew out of efforts to construct more efficient he...