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energy

(Encyclopedia)CE5 Relations between potential energy (PE) and kinetic energy (KE) for a swinging pendulum energy, in physics, the ability or capacity to do work or to produce change. Forms of energy include hea...

state of emergency

(Encyclopedia)state of emergency, situation in which a government or a government body is empowered to act with enhanced powers in order to respond to a crisis. The enhanced or emergency powers, and in many cases i...

air, law of the

(Encyclopedia)air, law of the, in the broadest sense, all law connected with the use of the air, including radio and satellite transmissions; more commonly, it refers to laws concerning civil aviation. The developm...

Lenz's law

(Encyclopedia)Lenz's law, physical law, discovered by the German scientist H. F. E. Lenz in 1834, that states that the electromotive force (emf) induced in a conductor moving perpendicular to a magnetic field tends...

field, in physics

(Encyclopedia)field, in physics, region throughout which a force may be exerted; examples are the gravitational, electric, and magnetic fields that surround, respectively, masses, electric charges, and magnets. The...

American Academy and Institute of Arts and Letters

(Encyclopedia)American Academy and Institute of Arts and Letters, honorary academy of notable American artists, writers, and composers. The National Institute of Arts and Letters, founded in 1898, served as the par...

Freedom of Information Act

(Encyclopedia)Freedom of Information Act (1966), law requiring that U.S. government agencies release their records to the public on request, unless the information sought falls into a category specifically exempted...

Michelson, Albert Abraham

(Encyclopedia)Michelson, Albert Abraham mīˈkəlsən [key], 1852–1931, American physicist, b. Strelno, Prussia, grad. Annapolis, 1873, and studied at Berlin, Heidelberg, and Paris. He was professor of physics at...

Securities and Exchange Commission

(Encyclopedia)Securities and Exchange Commission (SEC), agency of the U.S. government created by the Securities Exchange Act of 1934 and charged with protecting the interests of the public and investors in connecti...

Rhodesia and Nyasaland, Federation of

(Encyclopedia)Rhodesia and Nyasaland, Federation of, SE Africa, 1953–63, composed of the self-governing British colony of Southern Rhodesia and the British protectorates of Northern Rhodesia and Nyasaland. The ca...