Gamma Rays

NCERT Class 12, Chapter 8 (Electromagnetic Waves) places gamma rays at the extreme high-frequency, short-wavelength end of the spectrum, with wavelengths below about 10⁻¹² m. Because photon energy is proportional to frequency (E = hf), gamma rays carry the greatest energy per photon of all electromagnetic radiations. They are produced in nuclear reactions and radioactive decay, when an excited nucleus drops to a lower energy state and releases the excess as a high-energy photon. Microwaves have low frequencies and are generated by electronic oscillators, not nuclei, so their photon energy is far smaller. Visible light arises from electronic transitions in atoms and molecules and carries only a few electronvolts per photon. Infrared radiation, associated with molecular vibrations and thermal emission, has even lower photon energy. A plausibility check comparing photon energies confirms that gamma rays, tied to nuclear transitions, dominate all the listed options in energy, making them the correct choice.