A source of monochromatic light liberates 9 \( \times \) 1020 photon per second with wavelength 600 nm when operated at 400 W. The number of photons emitted per second with wavelength of 800 nm by the source of monochromatic light operating at same power will be :
A source of monochromatic light liberates 9 \( \times \) 1020 photon per second with wavelength 600 nm when operated at 400 W. The number of photons emitted per second with wavelength of 800 nm by the source of monochromatic light operating at same power will be :
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- 12 \( \times \) 1020
- 6 \( \times \) 1020
- 9 \( \times \) 1020
- 24 \( \times \) 1020
The Correct Option is A
Solution and Explanation
Step 2: For the same power, n2/n1 = \(\lambda\)2/\(\lambda\)1 = 800/600 = 4/3.
Step 3: n2 = 9 × 1020 × 4/3 = 12 × 1020 photons per second.
Answer: (A) 12 × 1020
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