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 - Physics

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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

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Solution

Energy = hν

power is the energy per unit time  therfore the energy given per second is  = `2xx10^-3`

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 

Concept: Refraction of Monochromatic Light
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2013-2014 (March) Delhi Set 1

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