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A moncohromatic source of light operatin...

A moncohromatic source of light operating at 200 W emits `4xx10^(20)` photons per second. Find the wavelength of the light.

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Power `P=(n)/(t)(hc)/(lamda)`
Energy of Photon `E=(P)/((N/(t)))=(200)/(4xx10^(20))=5xx10^(-19)J`
`lamda=4xx10^(20)xx(6.6xx10^(-34)xx3xx10^(8))/(200)=3960Å`
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AAKASH SERIES-DUAL NATURE OF RADIATION AND MATTER-PRACTICE EXERCISEX
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