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The number of photons falling per second...

The number of photons falling per second on a completely darkened plate to produce force of `6.62xx10^(-5) N` is n . If the wavelength of the light falling is `5xx10^(-7)` m then n = ............ `xx 10^(22)`.
( `h = 6.62 xx10^(-34)J s` )

A

1

B

5

C

0.2

D

3.3

Text Solution

Verified by Experts

The correct Answer is:
B
`P=n/t*(hc)/lamda`
`FC=n/t*(hC)/lamda`
`n/t=(Flamda)/h`
`n/t=(6.62xx10^(-5)xx5xx10^(-7))/(6.62xx10^(-34))`
= `5xx10^(22)`
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