Q.Who discovered X-rays? Write two properties and two important uses of X-rays.

X-rays are electromagnetic waves of very short wavelength.

X-rays are produced when fast electrons are suddenly decelerated on striking a metal target, but the X-rays themselves are electromagnetic radiation — transverse waves of oscillating electric and magnetic fields travelling at the speed of light. Their wavelength (about 0.01–10 nm) is much shorter …

X-rays are used to examine crystal structure because their wavelength matches the spacing between atomic planes in a crystal, producing a measurable diffraction pattern.

X-rays have wavelengths of the order of 0.1-1 Angstrom (10^-11 to 10^-10 m), comparable to the spacing between atomic planes in a crystal lattice. When X-rays are incident on a crystal, they get diffracted by the regularly-spaced atoms according to Bragg's law, $2d\sin\theta = n\lambda$, producing a diffraction pattern that reveals the crystal's internal atomic arrangement. Th …

X-rays are electromagnetic waves of very short wavelength.

X-rays are electromagnetic radiation with wavelengths of about $0.01$–$10$ nm (frequency ~$10^{16}$–$10^{19}$ Hz), lying between ultraviolet and gamma rays in the electromagnetic spectrum. They are not streams of charged particles; they are uncharged, travel at the speed of light in vac …

X-rays were discovered by Wilhelm Conrad Röntgen in 1895 while experimenting with cathode-ray (discharge) tubes, for which he received the first-ever Nobel Prize in Physics (1901).

Röntgen noticed that a fluorescent screen kept some distance from a discharge tube (covered in black paper so no visible or cathode-ray light could escape) still glowed, revealing an unknown, highly penetrating radiation that he called 'X-rays' because their nature was then unknown.

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Between UV and gamma rays lie X-rays.

The question asks which electromagnetic wave is used as a diagnostic tool in medicine. X-rays are the correct choice because they penetrate soft tissue but are absorbed by denser materials like bone, making them ideal for imaging fractures and internal structures. The answer is (A) X-rays.

Radiography uses X-rays, the high-frequency, short-wavelength part of the electromagnetic spectrum.

The electromagnetic spectrum contains, in order of increasing frequency (decreasing wavelength): radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and $\gamma$-rays. X-rays have wavelengths roughly in the range $10^{-8}$ m to $10^{-13}$ m and correspondingly very high photon energies. This gives them strong penetrating power through soft materials (flesh, cloth) while being significantly absorbed by denser materials (bones, metals). This …