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Definition
| A traveling disturbance that carries energy from one place to another w/o requiring matter to travel across the intervening distance |
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Definition
| The distance between adjacent wave crests, the highest points of adjacent waves |
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Definition
| (Measured in Hertz) The number of wave crests that go by a given point every second. A wave completing one cycle (sending one crest by a point every second) has a frequency oof pne hertz, 1 Hz. |
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Definition
| When waves from two different sources come together at a single point, they interfere w/ each other. The observed wave amplitude is the sum of the amplitudes of the interfereing waves. |
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Term
| Electromagnetic wave, or electromagnetic radiation |
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Definition
| A form of radiant energy that reacts w/ matter by being transmitted, absorbed, or scattered. A self-propagating wave made up of electric and magnetic fields fluctuating together. A wave created when electrical charges accelerate, but requiring no medium for transfer. |
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Definition
A form of electromagnetic wave to which the human eye is sensitive. Light travels at a constant speed and needs no medium for transfer. |
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Definition
| The velocity at which all electromagnetic waves travel, regardless of their wavelength or fequency; equal to 300,000 kilometers per sec. (186,000 miles per sec) |
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Definition
| The change in frequency or wavelength of a wave by an observer because the source of the wave is moving. |
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Definition
| One of three responses of an electromagnetic wave encountering matter, in which ligt energy passes through the matter unaffected. |
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Definition
| One of three responses of an electromagnetic wave encoutering matter, in which electromagnetic waves slow down and change direction in the matter. |
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Definition
| One of three possible responses of an electromagnetic wave encountering matter, in which light energy is converted into some other form, usually heat energy. |
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Definition
| A process by which light waves are absorbed and reemitted in all directions by a medium such as clouds or snow. |
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Definition
| A process by which light waves are scattered at the smae angle and the original wave; for example, from the surface of a mirror. |
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Definition
The entire array of waves, varying in frequency and wavelength, but all resulting from an accelerating electrical charge; includes radio waves, microwaves, infrared, visable light, ultraviolet, X-rays, gamma rays, and others. |
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Definition
| Part of the elecromagnetic spectrum that ranges from the longest waves-- wavelengths longer than Earth's diameter-- to waves a few meters long. |
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Definition
| Electromagnetic waves, w/ wavelengths ranging from approximately 1 meter to 1 millimeter, which are used extensively for line-of-sight communications and cooking. |
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Definition
| Wavelengths of electromagnetic radiation that extend from a millimeter to a micron, felt as heat radiation. |
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Definition
| Electromagnetic waves w/ a wavelength that can be interpreted by nerve receptors in the brain; wavelengths range from 700 nanometers for a red light to 400 nanometers for a violet light. |
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Definition
| Hight-frequency wavelengths, shorter than visable light, ranging from 400 nanometers to 100 nanaometers. |
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Definition
| High-frequency and high-E elecromagnetic waves that range in wavelength from 100 nano meters to 0.1 nanometer, used in medicine and industry. |
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Definition
| The highest-E wave of the electromagnetic spectrum w/ wavelengths less than the size of an atom, less than one-trillionth of a meter; normally emitted in very high-E nuclear particle reactions. |
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Term
| Frequency Modulation (FM) |
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Definition
| A process by which information is transmitted by verying the frequency of a signal. After being transmitted, the signal may be converted to sound by circuits in a receiver. |
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Term
| Amplitude Modulation (AM) |
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Definition
| A process by which information is transmitted by verying the amplitude of a radio wave signal being tansmitted. After tansmission, the signal is converted to sound by the radio converter. |
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