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The eyes of certain member of the reptil...

The eyes of certain member of the reptile family pass a single visual signal to the brain when the visual receptors are struck by photons of wavelength `850nm`. If a total energy of `3.15xx10^(14)J` is required to trip the signal. What is the minimum number of photons that must strike the receptor?

Text Solution

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`E=(hc)/(lamda)`
`=(6.6xx10^(-34)xx3xx10^(8))/(850xx10^(-9))`
`=2.3xx10^(-19)J`
Energy required to trip signal `=3.15xx10^(-14)J`
`nxxE=E_("total")`
`n=(3.15xx10^(-14))/(2.3xx10^(-19))`
`n=1.37xx10^(5)` photons
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