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sunspots

(Encyclopedia)sunspots, dark, usually irregularly shaped spots on the sun's surface that are actually solar magnetic storms. The spots are darker because the temperature of the spots is lower than that of the surro...

symbolic logic

(Encyclopedia)symbolic logic or mathematical logic, formalized system of deductive logic, employing abstract symbols for the various aspects of natural language. Symbolic logic draws on the concepts and techniques ...

radio

(Encyclopedia)CE5 A. AM transmitter B. AM receiver radio, transmission or reception of electromagnetic radiation in the radio frequency range. The term is commonly applied also to the equipment used, especially...

transistor

(Encyclopedia)CE5 Simple transistor circuit transistor, three-terminal, solid-state electronic device used for amplification and switching. It is the solid-state analog to the triode electron tube; the transist...

Hitler, Adolf

(Encyclopedia)Hitler, Adolf äˈdôlf hĭtˈlər [key], 1889–1945, founder and leader of National Socialism (Nazism), and German dictator, b. Braunau in Upper Austria. By July, 1944, the German military si...

psychology

(Encyclopedia)psychology, science or study of the thought processes and behavior of humans and other animals in their interaction with the environment. Psychologists study processes of sense perception, thinking, l...

Metternich, Clemens Wenzel Nepomuk Lothar, Fürst von

(Encyclopedia)Metternich, Clemens Wenzel Nepomuk Lothar, Fürst von klāˈmĕns vĕnˈtsəl nāˈpōmo͝ok lōˈtär fürst fən mĕtˈərnĭkh [key], 1773–1859, Austrian statesman and arbiter of post-Napoleonic ...

song

(Encyclopedia)song, relatively brief, simple vocal composition, usually a setting of a poetic text, often strophic, for accompanied solo voice. The song literature of Western music embodies two broad classification...

turtle

(Encyclopedia)turtle, a reptile of the order Chelonia, with strong, beaked, toothless jaws and, usually, an armorlike shell. The shell normally consists of bony plates overlaid with horny shields. The upper portion...

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