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time , sequential arrangement of all events

(Encyclopedia)time, sequential arrangement of all events, or the interval between two events in such a sequence. The concept of time may be discussed on several different levels: physical, psychological, philosophi...

jet stream

(Encyclopedia)jet stream, narrow, swift currents or tubes of air found at heights ranging from 7 to 8 mi (11.3–12.9 km) above the surface of the earth. They are caused by great temperature differences between adj...

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...

submarine

(Encyclopedia)submarine, naval craft capable of operating for an extended period of time underwater. Submarines are almost always warships, although a few are used for scientific, business, or other purposes (see a...

universe

(Encyclopedia)universe, totality of matter and energy in existence. The study of the origin of the universe, or cosmos, is known as cosmogony, and that of its structure and evolution, cosmology. The age of the univ...

propeller

(Encyclopedia)propeller, device consisting of a hub with one or more blades that propels a craft to which it is attached by rotating its blades in a fluid such as air or water. In the latter part of the 1830s the S...

jet propulsion

(Encyclopedia)CE5 Types of jet engines: In the propeller-driven turbine a stream of high-velocity gases provides the power to drive the turbine and turn the propeller. In the jet-driven turbine the stream of gas...

Bucephalus

(Encyclopedia)Bucephalus byo͞osĕˈfələs [key], favorite horse of Alexander the Great. There are legends of his speed and the wondrous deeds that Alexander performed while riding him. He died in 326 b.c. after t...

West Allis

(Encyclopedia)West Allis, city (1990 pop. 63,221), Milwaukee co., SE Wis., a residential and industrial suburb of Milwaukee; inc. 1902. It is a banking center, and there is food processing and the manufacture of mo...