Concept:Across the electromagnetic spectrum, wavelength decreases as photon energy and frequency increase.
Formula / Reaction:$$\lambda_{\gamma} < \lambda_{\text{X-ray}} < \lambda_{\text{UV}} < \lambda_{\text{Visible}} < \lambda_{\text{IR}} < \lambda_{\text{Micro}} < \lambda_{\text{Radio}}$$
Solution:- Gamma rays have the highest frequencies (\(> 10^{19}\text{ Hz}\)) and the shortest wavelengths (\(\lambda < 10^{-11}\text{ m}\) or \(< 0.01\text{ nm}\)).
- Therefore, gamma rays have the smallest wavelength among all electromagnetic waves.
Why other options are incorrect:- Opt_A: X-rays have wavelengths around \(0.01\text{ nm to }10\text{ nm}\), which are longer than gamma rays.
- Opt_C: Microwaves have long wavelengths (\(1\text{ mm to }1\text{ m}\)).
- Opt_D: Ultraviolet rays have wavelengths between \(10\text{ nm}\) and \(400\text{ nm}\).
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