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Monochromatic light of frequency 6.0 × 10^{14} Hz is produced by a laser. The power emitted is 2.0 × 10^{−3} W. Estimate the number of photons emitted per second on an average by the source

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#### Solution

Energy = hν

On putting the values, we get:

number of photons * energy of one photon = total energy

number of photons=`(2xx10^-3)/(6.63xx10^-34xx6xx10^14)`

=`5 xx 10^15` photons

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