Arrange the following electromagnetic waves in the increasing order of their energy.
(A) infrared rays
(B) AM radio waves
(C) \( \gamma \)-rays
(D) Microwaves
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → (B), (D), (A), (C)
The energy of a photon is \( E = h\nu \), so the energy increases with frequency, that is, as the wavelength decreases along the electromagnetic spectrum.
The spectrum, in order of increasing frequency, runs: radio waves, microwaves, infrared, visible, ultraviolet, X-rays, \( \gamma \)-rays.
\( (B)\ \text{AM radio waves} \lt (D)\ \text{Microwaves} \lt (A)\ \text{infrared rays} \lt (C)\ \gamma\text{-rays} \)
The increasing order is B, D, A, C.
NCERT (2026-27):
Summary – “… The spectrum of electromagnetic waves stretches, in principle, over an infinite range of wavelengths. 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.”