Assuming human pupil to have a radius of 0.25 cm and a comfortable viewing distance of 25 cm, the minimum separation between two objects than human eye can resolve at 500nm wavelength is :

Options

A. `1 mu m`
B. `30 mu m`
C. `100 mu m`
D. `300 mu m`

Answer

B

Explanation

`sin theta = (0.25)/(25) = (1)/(100)`
Resolving power of eye is
`RP = (1.22 lamda)/(2 mu sin theta) = (1.22 xx(500 xx 10^-9))/(2 xx 1 xx(1//100))`
=`3.05 xx 10^-5 m`
`~~ 30 mu m`.
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