The following sections of this BookRags Literature Study Guide is offprint from Gale's For Students Series: Presenting Analysis, Context, and Criticism on Commonly Studied Works: Introduction, Author Biography, Plot Summary, Characters, Themes, Style, Historical Context, Critical Overview, Criticism and Critical Essays, Media Adaptations, Topics for Further Study, Compare & Contrast, What Do I Read Next?, For Further Study, and Sources.
(c)1998-2002; (c)2002 by Gale. Gale is an imprint of The Gale Group, Inc., a division of Thomson Learning, Inc. Gale and Design and Thomson Learning are trademarks used herein under license.
The following sections, if they exist, are offprint from Beacham's Encyclopedia of Popular Fiction: "Social Concerns", "Thematic Overview", "Techniques", "Literary Precedents", "Key Questions", "Related Titles", "Adaptations", "Related Web Sites". (c)1994-2005, by Walton Beacham.
The following sections, if they exist, are offprint from Beacham's Guide to Literature for Young Adults: "About the Author", "Overview", "Setting", "Literary Qualities", "Social Sensitivity", "Topics for Discussion", "Ideas for Reports and Papers". (c)1994-2005, by Walton Beacham.
All other sections in this Literature Study Guide are owned and copyrighted by BookRags, Inc.
Light, also known as visible radiation, is electromagnetic radiation within the wavelength band that can be perceived by the human eye. This range is from about 380-780 nanometers (or nm; 1 nm = 10-9 m). Wavelengths shorter than the lower end of the visible range are known as ultraviolet, and longer ones are infrared.
The electromagnetic spectrum of visible radiation is commonly partitioned into a number of sub-ranges, which correspond to the "colors of the rainbow": red, orange, yellow, green, blue, and violet. These colors have the following wavelength ranges: red, 740-620 nm; orange, 620-585 nm; yellow, 585-575 nm; green, 575-500 nm; blue, 490-445 nm; violet, 445-390 nm.
Sometimes, the word "light" is also used in reference to the entire electromagnetic spectrum, or to components such as gamma, X-ray, ultraviolet, infrared, microwave, or radio. In the physical sense, however, this is an inappropriate use of the word light, which should be restricted to wavelengths in the range of 380 to 780 nm.