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Monochromatic light of frequency 6.0×10 14 Hz is produced by a laser. The power emitted is 2×10 -3 W. The number of photons emitted, on an average, by the source per second is n × 10 15 where n is an integer. Find the value of n ?

Correct answer

5

Step-by-step solution

P = 2 × 10 - 3 W Energy of photon, E = h v = 6.6 × 10 - 34 × 6 × 10 14 J Where h being Planck's constant. Number of photons emitted per second n = p E = 2 × 10 - 3 6.6 × 10 - 34 × 6 × 10 14 = 5 × 10 15

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