Arrange the given associated wavelengths ($λ_1, λ_2, λ_3$ and $λ_4$) of radiations with the part of the electromagnetic spectrum in decreasing order of magnitude:

(A) $λ_1$ used to detect fracture in bones
(B) $λ_2$ used to kill germs in water purifiers
(C) $λ_3$ used to treat muscular strain
(D) $λ_4$ used to transmit voice communication

Choose the correct answer from the options given below:

(D), (C), (B), (A)

The correct answer is Option (1) → (D), (C), (B), (A)

Analysis of radiations:

(A) X-rays – used to detect fracture in bones – λ1 ≈ 10⁻¹⁰ m

(B) UV rays – used to kill germs – λ2 ≈ 10⁻⁸ m

(C) Infrared rays – used to treat muscular strain – λ3 ≈ 10⁻⁵ m

(D) Radio waves – used to transmit voice communication – λ4 ≈ 1 m

Arrange in **decreasing order of wavelength**:

λ4 (Radio) > λ3 (Infrared) > λ2 (UV) > λ1 (X-ray)

Decreasing order: λ4, λ3, λ2, λ1