Concept:The electromagnetic spectrum in order of increasing frequency (and increasing photon energy) begins at radio waves and ends at gamma rays.
Formula / Reaction:$$f_{\text{Radio}} < f_{\text{Micro}} < f_{\text{IR}} < f_{\text{Visible}} < f_{\text{UV}} < f_{\text{X-ray}} < f_{\text{Gamma}}$$
Solution:- Radio waves: \(f \sim 10^4 - 10^9\text{ Hz}\).
- Infrared: \(f \sim 10^{11} - 10^{14}\text{ Hz}\).
- Visible: \(f \sim 4 \times 10^{14} - 7.5 \times 10^{14}\text{ Hz}\).
- Ultraviolet: \(f \sim 10^{15} - 10^{16}\text{ Hz}\).
- Gamma rays: \(f > 10^{19}\text{ Hz}\).
Why other options are incorrect:- Opt_A: Listed in order of decreasing frequency.
- Opt_C: Incorrectly places microwaves before radio waves.
- Opt_D: Incorrectly places visible before infrared and ultraviolet.
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