Arrange the electromagnetic waves which have the following applications in the decreasing order of their wavelengths.
A. to treat muscular strain.
B. for broadcasting
C. to detect bone fractures
D. absorbed by the ozone layer of the atmosphere
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → B, A, D, C
First identify the radiation used for each application, then place it in the electromagnetic spectrum, where the wavelength decreases from radio waves to gamma rays.
\( \text{(B) broadcasting: radio waves, } \lambda \gt 0.1\,\mathrm{m} \)
\( \text{(A) treating muscular strain: infrared, about } 10^{-6}\,\mathrm{m} \)
\( \text{(D) absorbed by the ozone layer: ultraviolet, about } 10^{-8}\,\mathrm{m} \)
\( \text{(C) detecting bone fractures: X-rays, about } 10^{-10}\,\mathrm{m} \)
So the decreasing order of wavelength is (B), (A), (D), (C).
NCERT (2026-27):
Electromagnetic Spectrum – “… We briefly describe these different types of electromagnetic waves, in order of decreasing wavelengths.”
Radio Waves – “… They are used in radio and television communication systems.”
Infrared Waves – “… Infrared lamps are used in physical therapy.”
Ultraviolet Rays – “… The sun is an important source of ultraviolet light. But fortunately, most of it is absorbed in the ozone layer in the atmosphere at an altitude of about 40 – 50 km.”
X-Rays – “… X-rays are used as a diagnostic tool in medicine and as a treatment for certain forms of cancer.”