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Light of wavelength 5000Å and intensity...

Light of wavelength `5000Å` and intensity `39.8Wm^(-1)` is incident on a metal surface. If only 1% photons of incident light emit photoelectrons, then the number of electrons emitted per second per unit area from the surface will be nearly :

A

`10^(18)`

B

`10^(20)`

C

`10^(22)`

D

`10^(24)`

Text Solution

Verified by Experts

The correct Answer is:
A

`E=nh rArr E=(nhc)/(lambda)`
`rArr n=(E lambda)/(hc)`
But `n=(n)/(100)=(E lambda)/(100 hc)=10^(18)`
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