A 25 Watt Bulb Emits Monochromatic Yellow Light Of Wavelength Of 0.57 μm. Calculate The Rate Of Emission Of Quanta Per Second.

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A 25 watt bulb emits monochromatic yellow light of wavelength of 0.57 μm. Calculate the rate of emission of quanta per second.


Correct option is


Energy emitted by the bulb = 25 watt = 25 J s–1  (∵ 1 watt = 1 Js–1

Energy of one photon (E) = hv   






∴ No. of photons emitted per sec  





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