A 2 mW laser operates at a wavelength of 500 nm. The number of photons that will be emitted per second is: [Given Planck's constant h=6.6 10^-34 Js speed of light (c=3.0 10^8m/s)

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Correct answer: A. (a) JEE Main 2019 Energy of photon (E ) is given by E= hc Number of photons of wavelength emitted in t second from laser of power P is given by n= Ptλ hc ⇒n= 2 hc= 2 10^-3 5 10^-72 10^-25 ( ∵t=1S ) ⇒n=5 10^15

$A 2 mW laser operates at a wavelength of 500 nm . The number of photons that will be emitted per second is: [Given Planck's constant h = 6.6 \times 10^{- 34} Js speed of light (c = 3.0 \times 10^{8} m / s)$

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