Rontgen ray

[Sarah]

Any of the rays produced when cathode rays strike upon surfaceof a solid (as the wall of the vacuum tube). Röntgen rays are notedfor their penetration of many opaque substances, as wood and flesh,their action on photographic plates, and their fluorescent effects.They were called X rays by their discoverer, W. K. Röntgen. They alsoionize gases, but cannot be reflected, or polarized, or deflected bya magnetic field. They are regarded as nonperiodic, transverse pulsesin the ether. They are used in examining opaque objects, as forlocating fractures or bullets in the human body.