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A monochromatic source of light operatin...

A monochromatic source of light operating at 200W
emits `4 xx 10^20` photons per second. Find the wavelength
of the light.

Text Solution

Verified by Experts

The energy of each photon `=(200(J)/(s))/((4xx10^(20))/(s))=5xx10^(-19)J`
Wavelength `=lamda=(hc)/(E)`
`=((6.63xx10^(-34)J-s)xx(3xx10^(8)(m)/(s)))/((5xx10^(-19)J))`
`=4.0xx10^(-7)`m
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