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Question
Monochromatic light of frequency 6.0 × 1014 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
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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