Two point white dots are 1mm apart on a black paper. They are viewed by eye of pupil diameter 3mm. Approximately, what is the maximum distance at which these dits can be resolved by the eye? [Take wavelelngth of light =500nm]

Options

A. `6m`
B. `3m`
C. `5m`
D. `1m`

Answer

C

Explanation

Resolving limit of eye `theta`
`= (1.22lambda)/(d) = (1.22xx500xx10^(-9))/(3xx10^(-3)) = 2xx10^(-4) rad`

`theta = (x)/(d)`
`2xx10^(-4) = (1)/(d)`
`d = 5000mm = 5m`