Match List I with List II
| LIST I Phenomenon | LIST II Scientists | ||
|---|---|---|---|
| A. | Dispersion of white light | I. | Cassegrain |
| B. | Reflecting type telescope | II. | Huygens |
| C. | Double slit experiment | III. | Newton |
| D. | Wavefront | IV. | Thomas Young |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → A-III, B-I, C-IV, D-II
Each phenomenon or instrument is linked with the scientist who discovered or devised it.
(A) Dispersion of white light — this matches (III) Newton. Newton used a prism to split white light into its colours and showed that the colours are in the light itself.
(B) Reflecting type telescope — this matches (I) Cassegrain. In the Cassegrain design a concave primary mirror and a convex secondary mirror form the image, which is viewed through a hole in the primary.
(C) Double slit experiment — this matches (IV) Thomas Young. Young's experiment of 1801 showed interference of light and supported the wave theory.
(D) Wavefront — this matches (II) Huygens. Huygens's principle describes how a wavefront moves forward, each point on it acting as a source of secondary wavelets.
Note: Pairs (B), (C) and (D) of this question are from the latest textbook (2026-27). Pair (A), that Newton showed the dispersion of white light, is printed only in the pre-rationalised textbook (2022-23). It was removed from the latest book, but dispersion through a prism is still in the CUET 2026 syllabus, so do not skip it.
NCERT (2026-27):
Telescope – “… This is known as a Cassegrain telescope, after its inventor.”
Introduction – “… However, when Thomas Young performed his famous interference experiment in 1801, it was firmly established that light is indeed a wave phenomenon.”
Huygens Principle – “… Now, if we know the shape of the wavefront at t = 0, then Huygens principle allows us to determine the shape of the wavefront at a later time t.”
NCERT (Pre-rationalised edition, 2022-23):
Dispersion by a Prism – “… In a classic experiment known for its simplicity but great significance, Isaac Newton settled the issue once for all. … Thus, white light itself consists of light of different colours, which are separated by the prism.”