
The correct assignment of P, Q, and R to electromagnetic waves requires an understanding of the relationship between wavelength, energy, and their position within the electromagnetic spectrum.
Within the electromagnetic spectrum, energy and wavelength are inversely proportional: increased energy corresponds to decreased wavelength, and vice versa. Based on this:
Consequently, the accurate sequence is: X-rays, UV radiation, microwaves.
| List I: Frequency Range | List II: Types of Waves |
|---|---|
| (I) 1 × 1016 − 3 × 1021 Hz | (D) γ-rays |
| (II) 1 × 109 − 3 × 1011 Hz | (B) Microwaves |
| (III) 1 × 108 − 5 × 1022 Hz | (A) X-rays |
| (IV) 5 × 105 − 109 Hz | (C) Radio waves |