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The mean wavelength of light from sun is...

The mean wavelength of light from sun is taken to be 550 nm and its mean power is `3.8 xx 10^(26)` W. The number of photons received by the human eye per second on the average from sunlight is of the order of………………

A

`10^(45)`

B

`10^(42)`

C

`10^(54)`

D

`10^(51)`

Text Solution

Verified by Experts

The correct Answer is:
A
`P = (n)/(t) (hc)/(lambda)`
`therefore" "(n)/(t) = (P lambda)/(hc) = (3.8 xx 10^(26) xx 550 xx 10^(-9))/(6.6 xx 10^(-34) xx 3 xx 10^(8)) = 1 xx 10^(45)`
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