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Minimum light intensity that can be perc...

Minimum light intensity that can be perceived by normal human eye is about `10^(-10) Wm^(-2)`. What is the minimum number of photons of wavelength 660 nm that must enter the pupil in one second, for one to see the object?Area of cross-section of the pupil is `10^(-4)m^(2)`?

A

`3.318 xx 10^(3)`

B

`1.453 xx 10^(3)`

C

`3.38 xx 10^(4)`

D

`1.453 xx 10^(5)`

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