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Find the number of photons entering the ...

Find the number of photons entering the pupil of our eye per second corresponding to the minimum internsity of white light that we humans can perceive `(-10^(-10) Wm^(-2))`. Take the area of the pupil to be about `0.4 cm^(2)`, and the average frequency of white light to be about `6xx10^(14) Hz`.

A

around `1xx10^4`in 1s

B

around 100 in 1s

C

around 1000 in 1s

D

only 1 in 1s

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The correct Answer is:
A
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