What is the correct increasing order of the wavelengths of the following…
2024
What is the correct increasing order of the wavelengths of the following components of solar radiation?
(A) Visible light
(B) Microwaves
(C) Infra-red rays
(D) Ultra-violet rays
Choose the correct answer from the options given below:
Answer: D. (D), (A), (C), (B) — ConceptElectromagnetic radiation is arranged by increasing wavelength from shorter-wave bands to longer-wave bands. Across the relevant part of the spectrum,…
- A.
(C), (D), (B), (A)
- B.
(A), (B), (D), (C)
- C.
(D), (A), (B), (C)
- D.
(D), (A), (C), (B)
Show answer & explanation
Correct answer: D
Concept
Electromagnetic radiation is arranged by increasing wavelength from shorter-wave bands to longer-wave bands. Across the relevant part of the spectrum, the order is ultra-violet, visible, infra-red, and microwave.
Wavelength and frequency are inversely related by c = fλ, so a lower frequency corresponds to a longer wavelength.
Application
Identify the relative positions: ultra-violet comes before visible light; visible light comes before infra-red; infra-red comes before microwaves.
Combine these comparisons into one increasing-wavelength sequence: ultra-violet rays → visible light → infra-red rays → microwaves.
Thus the required sequence by value is ultra-violet rays, visible light, infra-red rays, and microwaves.
Cross-check
Radiation band | Approximate wavelength |
|---|---|
Ultra-violet | 10–400 nm |
Visible light | 400–700 nm |
Infra-red | 700 nm–1 mm |
Microwave | 1 mm–1 m |
The successive wavelength bands increase at every transition, independently confirming the sequence.
Result
Ultra-violet rays → visible light → infra-red rays → microwaves.