Match the LIST-I with LIST-II
| LIST-I (Discoveries) | LIST-II (Scientist) |
| A. Photoelectric emission was discovered by | I. Albert Einstein |
| B. X-rays were discovered by | II. Heinrich Hertz |
| C. Quantum nature of electromagnetic radiation was discovered by | III. Louis Victor de Broglie |
| D. Wave nature of matter was discovered by | IV. Roentgen |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → A-II, B-IV, C-I, D-III
The key discoveries of the dual nature of radiation and matter:
(A) Photoelectric emission was discovered by — this matches (II) Heinrich Hertz. In 1887, while studying electromagnetic waves, Hertz found that ultraviolet light on the spark gap made the discharge easier.
(B) X-rays were discovered by — this matches (IV) Roentgen. W. C. Roentgen discovered X-rays in 1895.
(C) Quantum nature of electromagnetic radiation was discovered by — this matches (I) Albert Einstein. Einstein explained the photoelectric effect (1905) by treating light as a stream of photons of energy \( h\nu \), building on Planck’s quantum hypothesis.
(D) Wave nature of matter was discovered by — this matches (III) Louis Victor de Broglie. De Broglie proposed (1924) that a moving particle has a wavelength \( \lambda = h/p \); Davisson and Germer later confirmed it experimentally.
NCERT (2026-27):
Introduction – “… The discovery of X-rays by Roentgen in 1895, and of electron by J. J. Thomson in 1897, were important milestones in the understanding of atomic structure.”
Hertz’s Observations – “The phenomenon of photoelectric emission was discovered in 1887 by Heinrich Hertz (1857-1894), during his electromagnetic wave experiments.”
Einstein’s Photoelectric Equation: Energy Quantum of Radiation – “In 1905, Albert Einstein (1879-1955) proposed a radically new picture of electromagnetic radiation to explain photoelectric effect.”
Wave Nature of Matter – “… In 1924, the French physicist Louis Victor de Broglie (pronounced as de Broy) (1892-1987) put forward the bold hypothesis that moving particles of matter should display wave-like properties under suitable conditions.”