Choose the correct statements regarding infra red waves from the following.
(A) Infra red waves produced by hot bodies and molecules.
(B) This radiation is trapped by greenhouse gases such as CO2 and water vapour.
(C) These waves are used in earth satellites.
(D) Exposure to these radiation induces the production of more melanin.
(E) These radiations are used in eye surgery.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → (A), (B) and (C) only
(A) Infra red waves produced by hot bodies and molecules. — Correct. The thermal vibrations of atoms and molecules in a hot body emit infrared radiation.
(B) This radiation is trapped by greenhouse gases such as CO2 and water vapour. — Correct. The earth re-radiates the absorbed sunlight as infrared, and these gases trap it, which keeps the earth warm.
(C) These waves are used in earth satellites. — Correct. Infrared detectors in satellites are used for military purposes and to observe the growth of crops.
(D) Exposure to these radiation induces the production of more melanin. — Incorrect. It is ultraviolet radiation that induces more melanin and causes tanning.
(E) These radiations are used in eye surgery. — Incorrect. Eye surgery (LASIK) uses narrow beams of ultraviolet radiation.
NCERT (2026-27):
Infrared Waves – “… Infrared waves are produced by hot bodies and molecules.”
Infrared Waves – “… This radiation is trapped by greenhouse gases such as carbon dioxide and water vapour. Infrared detectors are used in Earth satellites, both for military purposes and to observe growth of crops.”
Ultraviolet Rays – “… Exposure to UV radiation induces the production of more melanin, causing tanning of the skin.”
Ultraviolet Rays – “… Due to its shorter wavelengths, UV radiations can be focussed into very narrow beams for high precision applications such as LASIK (Laser- assisted in situ keratomileusis) eye surgery.”