FlashlightFlashlight is a portable electric light in a metal, fiber, or plastic case. A typical flashlight consists of a light source, power source, case, and on-off switch. The light source is a lamp (light bulb). A reflector and a lens help to focus the light into a beam. Most flashlight lamps are incandescent, but small fluorescent lamps are sometimes used (see Electric Light). Dry-cell batteries provide the power for most flashlights. The first dry-cell flashlight was made about 1898 in New York City. See also Battery.
Contributor: William Hand Allen, M.S., Former Electrical Engineer, Rockwell International. Master Index
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