Who discovered X-Ray?

Correct option is D

The correct answer is (d) W. C. Roentgen

Explanation:

• Wilhelm Conrad Roentgen, a German physicist, discovered X-rays on November 8, 1895.

• While performing experiments with a Crookes tube (a vacuum tube) in his laboratory, he noticed a mysterious glow on a screen coated with barium platinocyanide nearby.

• He realized that some invisible rays were passing through the cardboard covering the tube and the air to reach the screen.

• Because he did not know the nature of these rays at the time, he used the mathematical designation "X" (for unknown), and the name stuck.

• For this groundbreaking discovery, Roentgen was awarded the very first Nobel Prize in Physics in 1901.

Information Booster:

• According to NCERT Class 12 Physics, X-rays are a form of electromagnetic radiation with very short wavelengths ($0.1$ to $10$ nanometers).

• X-rays are produced when high-speed electrons strike a metal target of high atomic weight.

• The first clinical X-ray was an image of Roentgen's wife's hand, clearly showing her finger bones and wedding ring.

Additional Knowledge:

Galileo Galilei (Option a) * Known as the "Father of Observational Astronomy", he pioneered the use of the telescope to observe Jupiter's moons and the phases of Venus.

• He is not associated with the discovery of electromagnetic radiation like X-rays.

J.J. Thomson (Option b) * A British physicist credited with the discovery of the electron in 1897 through his experiments with cathode ray tubes.

• He proposed the "Plum Pudding Model" of the atom.

Edwin Hubble (Option c) * A famous American astronomer who proved that the universe is expanding (Hubble's Law).

• He also demonstrated that many objects previously thought to be clouds of dust were actually galaxies beyond the Milky Way.