﻿ A 200 W sodium street lamp emits yellow light of wavelength 0.6 um. Assuming it to be 25% efficient in converting electrical energy to light, the number of photons of yellow light it emits per second is from Physics Work, Energy and Power Class 11 Manipur Board

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A 200 W sodium street lamp emits yellow light of wavelength 0.6 um. Assuming it to be 25% efficient in converting electrical energy to light, the number of photons of yellow light it emits per second is

• 1.5 x 1020

• 6 x 1018

• 62 x 1020

• 3 x1019

A.

1.5 x 1020

Efficient power P= Efficient power P= 1028 Views

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