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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^(53)`

Text Solution

Verified by Experts

The correct Answer is:
a
`P=(n)/(t)(hc)/(lambda)`
therefore `(n)/(t)=(Plambda)/(hc)=(3.8xx10^(26)xx550xx10^(45))/(6.6xx10^(-34)xx3xx10^(8))`
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