The number of photons per second on an average emitted by the source of monochromatic light of wavelength 600 nm , when it delivers the power of 3.3 × - Physics MCQ NEET 2021 2026 | ExamTest.live

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The number of photons per second on an average emitted by the source of monochromatic light of wavelength 600 nm, when it delivers the power of 3.3 \times 1 0^{- 3} watt will be (h = 6.6 \times 1 0^{- 34} Js):

Solution & Step-by-step Explanation

Power P = n \times \frac{h c}{λ}, where n is the number of photons per second. n = \frac{P λ}{h c} n = \frac{3.3 \times 1 0 ^{- 3} \times 600 \times 1 0 ^{- 9}}{6.6 \times 1 0 ^{- 34} \times 3 \times 1 0 ^{8}} n = \frac{3.3 \times 600 \times 1 0 ^{- 12}}{19.8 \times 1 0 ^{- 26}} n = \frac{1980 \times 1 0 ^{- 12}}{19.8 \times 1 0 ^{- 26}} = 100 \times 1 0^{14} = 1 0^{16}

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The number of photons per second on an average emitted by the source of monochromatic light of wavelength 600 nm, when it delivers the power of 3.3 \times 1 0^{- 3} watt will be (h = 6.6 \times 1 0^{- 34} Js):

1 0^{16}

1 0^{15}

1 0^{18}

1 0^{17}

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