X

Source edition 1965. Please read the Introduction to find out about this dictionary and our plans for it. Caution, many entries have not been updated since the 1965 edition.
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X-band

A frequency band used in radar extending approximately from 5.2 to 10.9 kilomegacycles per second.

X-ray

Nonnuclear electromagnetic radiation of very short wavelength, lying within the interval of 0.1 to 100 angstroms (between gamma rays and ultraviolet radiation). Also called X-radiation, Roentgen ray .

X-rays penetrate various thickness of all solids and they act upon photographic plates in the same manner as light. Secondary X-rays are produced whenever X-rays are absorbed by a substance; in the case of absorption by a gas, this results in ionization.

X-radiation = X-ray.