Match List-I with List-II
| List-I | List-II |
| Application | Electromagnetic waves |
| (A) Used in radiography | (I) UV rays |
| (B) Detection by stimulating nerve endings of the human retina | (II) Microwaves |
| (C) Water purification | (III) Visible light |
| (D) Radar communication | (IV) X rays |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → (A) - (IV), (B) - (III), (C) - (I), (D) - (II)
Each band of the electromagnetic spectrum is used where its wavelength and penetrating power suit the job.
(A) Used in radiography — this matches (IV) X rays. X-rays penetrate soft tissue but are absorbed more by bone, so they form shadow images of the body.
(B) Detection by stimulating nerve endings of the human retina — this matches (III) Visible light. Visible light is, by definition, the band the eye can detect.
(C) Water purification — this matches (I) UV rays. Ultraviolet radiation kills germs, so UV lamps are used to purify water.
(D) Radar communication — this matches (II) Microwaves. Microwaves have short enough wavelengths to be sent in narrow beams, which suits radar.
NCERT (2026-27):
X-Rays – “… X-rays are used as a diagnostic tool in medicine and as a treatment for certain forms of cancer.”
Visible Rays – “… Visible light emitted or reflected from objects around us provides us information about the world. Our eyes are sensitive to this range of wavelengths.”
Ultraviolet Rays – “… UV lamps are used to kill germs in water purifiers.”
Microwaves – “… Due to their short wavelengths, they are suitable for the radar systems used in aircraft navigation.”