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BJU Physical Sci 14
BJU Physical Science - Ch 14
Question | Answer |
---|---|
The entire frequency continuum of electromagnetic waves. | electromagnetic spectrum |
The highest frequency band of electromagnetic energy, with frequencies extending upward from 30 EHz. They are produced by nuclear changes. | gamma ray |
The electromagnetic band extending from 300 GHz to about 384 THz, produced by the thermal motion of atoms and molecules. They support remote thermal imaging, “night vision,” and digital communications and control. | infrared |
A subset of the radio-frequency band of the electromagnetic spectrum extending from 100 MHz to 300 GHz. They support line-of-sight communications, high-speed data links, and high accuracy radar. | microwave |
A packet of electromagnetic energy. | photon |
Acronym for radio detection and ranging; a technology that uses electromagnetic waves to determine distance, direction, speed, or shape of an object by radio-wave echolocation. | radar |
The study of celestial objects by observing the radio waves they emit and the study of near-earth objects using active radar pulses. | radio astronomy |
Any method of navigation using radio signals. | radio navigation |
Electromagnetic waves in the frequency range extending from far below 300 Hz to 300 GHz, produced by the acceleration of electrons. They support television signals, radio signals, and radio astronomy. | radio wave |
Technology that uses radio frequency induction to generate an identification signal from a microprocessor receiver and antenna assembly. | radio-frequency identification |
The use of high-energy radiation to treat cancers. | radiotherapy |
The speed of any electromagnetic wave in a vacuum, approximately 3.00 × 10 to the 8th power m/s. | speed of light |
The electromagnetic band extending from 789 THz to 30 PHz, produced by the emission of photons during large changes of electron energy levels within atoms. | ultraviolet |
The band of electromagnetic frequencies human eyes can detect, extending from approximately 384 THz at the red end of the spectrum to 789 THz at the violet end. | visible light |
The electromagnetic band extending from 30 PHz to 30 EHz, although there is some overlap with gamma rays at the upper end. They are produced by high-energy collisions of electrons with atoms. | x-rays |