Question

X rays were discovered by
A.Wilhelm K. Roentgen.
B.H. Kissinger
C.Sir C. V. Raman
D.Meghnad saha

Answer 1

Hint: X rays are also called x radiations and which are a form of high energy electromagnetic radiations. They have a greater wavelength.

Complete answer:
An X-ray or X-radiation is a piercing form of high energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, equivalent to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 124 eV to 124 keV. X-ray wavelengths are shorter than those of UV rays and naturally longer than those of gamma rays.
X-rays were revealed in 1895 by Wilhelm Conrad Roentgen (1845-1923) who was a Professor at Wuerzburg University in Germany. Effective with a cathode-ray tube in his laboratory, Roentgen experiential a fluorescent glow of crystals on a table near his tube. The tube that Roentgen was working with composed of a glass envelope that is a bulb with positive and negative electrodes encapsulated in it. The air in the tube was evacuated and when a high voltage was applied, the tube would produce a fluorescent glow. Roentgen protected the tube with heavy black paper, and discovered a green colored fluorescent light produced by a material located a few feet away from the tube.

He found a conclusion that a new type of ray was being emitted from the tube. This ray was able to pass through the heavy paper coating and excite the phosphorescent materials in the room. He observed that the new ray could pass through most substances casting shadows of solid objects. Roentgen also found out that the ray could pass through the tissue of humans, but not bones and metal objects. One of Roentgen's first experiments late in 1895 was a film of the hand of his wife, Bertha. It is attractive that the first use of X-rays were for an industrial application, as Roentgen generated a radiograph of a set of weights in a box to demonstrate his colleagues.

Hence, the correct answer is option (A)

Note: X ray is a common imaging test which is used for decades. This will help to diagnose, monitor, and treat many medical conditions.