If a source of electromagnetic radiation having power $15 \mathrm{~kW}$ produces $10^{16}$ photons per second, the radiation belongs to a part of spectrum is.
(Take Planck constant $h=6 \times 10^{-34} \mathrm{Js}$ )
Solution
$$
\begin{aligned}
& \text { Energy of one photon }=\frac{\text { Power }}{\text { Photon frequency }} \\\\
& \mathrm{E}=\mathrm{h} v=\frac{15 \times 10^3}{10^{16}} \\\\
& \Rightarrow v=\frac{15 \times 10^{-13}}{6 \times 10^{-34}}=2.5 \times 10^{21}
\end{aligned}
$$
<br/><br/>So gamma Rays.
About this question
Subject: Physics · Chapter: Dual Nature of Matter and Radiation · Topic: Photoelectric Effect
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