Question:
U 4 A beam of monochromatic light of wavelength 6600A is
Last updated: 6/7/2023
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U 4 A beam of monochromatic light of wavelength 6600A is incident normally on a perfectly absorbing surface The power of the beam is 30 W The number of photons absorbed per second by the surface is 1 1018 2 1019 3 1020 4 1021