JEE Mains · Physics · STD 12 - 11. Dual nature of radiation and matter
A monochromatic source of light operating at \(15\) kW emits \(2.5\times 10^{22}\) photons/s. The region of an electromagnetic spectrum to which the emitted electromagnetic radiation belongs to ________. (Take \(h=6.6\times 10^{-34}\) J·s and \(c=3\times 10^8\) m/s).
- A Microwave
- B Infrared
- C Visible
- D Ultraviolet
Answer & Solution
Correct Answer
(D) Ultraviolet
Step-by-step Solution
Detailed explanation
Power of the source, \(P = 15 \text{ kW} = 15 \times 10^3 \text{ J/s}\) Number of photons emitted per second, \(n = 2.5 \times 10^{22} \text{ s}^{-1}\) Energy of one photon, \(E = \dfrac{P}{n} = \dfrac{15 \times 10^3}{2.5 \times 10^{22}} = 6 \times 10^{-19} \text{ J}\) Using…
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