Nitrogen laser produces a radiation at a wavelength of 337.1 nm. If the number of photons emitted is 5.6 × 1024, calculate the power of this laser.


Given:

Wavelength, λ = 337.1 nm


Number of photons = 5.6 × 1024


Energy, E = nhv = nhc/λ


Where


n = number of photons emitted


h = Planck’s constant


c = velocity of radiation


λ = wavelength of radiation


Substituting the values in the given expression of Energy [E]:


= {[5.6× 1024] × [6.626× 10-34] × [3× 108 ms-1]} / [337.1× 10-9m]


= [1.113168] / [337.1× 10-9m]


= 3.302× 106 J


Hence, the power of the laser is 3.302× 106 J.


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