Consider the following statements:
A. The wavelength of microwaves is greater than that of UV rays.
B. The wavelength of IR rays is less than that of UV rays.
C. The wavelength of microwaves is less than that of IR rays.
D. Gamma rays have the shortest wavelength in the electromagnetic spectrum.
Of the above statements,
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → A and D are true
In order of increasing wavelength the electromagnetic spectrum runs through gamma rays, X-rays, ultraviolet, visible, infrared, microwaves and radio waves.
A. The wavelength of microwaves is greater than that of UV rays. — True. Microwaves lie on the long-wavelength side of the visible band, while UV rays lie on its short-wavelength side.
B. The wavelength of IR rays is less than that of UV rays. — False. Infrared lies beyond the red end of the visible band, and ultraviolet lies beyond the violet end. So IR rays have the longer wavelength.
C. The wavelength of microwaves is less than that of IR rays. — False. Microwaves come after infrared in the order of increasing wavelength, so their wavelength is greater.
D. Gamma rays have the shortest wavelength in the electromagnetic spectrum. — True. Gamma rays stand first in the order of increasing wavelength, at the short-wavelength end of the spectrum.
NCERT (2026-27):
Summary – “… Different regions are known by different names; γ-rays, X-rays, ultraviolet rays, visible rays, infrared rays, microwaves and radio waves in order of increasing wavelength from 10–2 Å or 10–12 m to 106 m.”