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The human eye can barely detect a yellow...

The human eye can barely detect a yellow lings (`lamda=6000A`) that delivers `1.7xx10^(-18)`W to the retina. The number of photons per second falling on the eye is nearest to

A

`5xx10^(9)`

B

5000

C

50

D

5

Text Solution

Verified by Experts

The correct Answer is:
D
`n=(W)/(hc)=(1.7xx10^(-18)xx6000xx10^(-10))/(6.6xx10^(-34)xx3xx10^(8))`
`=(10^(24))/(2xx10^(-25))=5`
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