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 $3.3 \times 10^{-3}$ watt will be: ($h=6.6\times 10^{-34}$Js)
(1) $10^{18}$
(2) $10^{17}$
(3) $10^{16}$
(4) $10^{15}$ Continue reading The number of photons per second on an average ….