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The eye can detect 5xx10^(4) photons (m^...

The eye can detect `5xx10^(4)` photons `(m^2s)^(-1)` of green light (`lamda=5000A)`, whole ear can detect `10^(-13)Wm^(2)` . As a power detector, which is more sensitive and by what factor?

Text Solution

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`E=12375/5000=2.475` eV =`4xx10^(-19)` J
`l_"Eye"` =(Photon flux) x (Energy of photon) =`(5xx10^4)xx(4xx10^(-19))approx 2xx10^(-14) (W//m^2)`
Lesser the intensity `rArr ` More sensitive .
`S_"Eye"/S_"Ear"=l_"Ear"/l_"Eye"=10^(-13) /(2xx10^(-14))=5`
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