A telescop with an objective aperture `0.25` m is uded to obseve two stars. If the wavelength of light used is `5000Å` . Find the minimum angular sepration between them.

Options

A. `2.44xx10^(-6)` rad
B. `2.44xx10^(-5)` rad
C. `1.22xx10^(-7)` rad
D. `1.22xx10^(-4)` rad

Answer

A

Explanation

`D=0.25m`
`lambda=Å=5xx10^(-7)m`
The minimum angular separation for a telescop is give by
`theta=(1.22lambda)/(D)=(1.22xx5xx10^(-7))/(0.25)`
`=(122xx10^(-2)xx5xx10^(-7))/(5)`
`=244xx10^(-7)` rad
`theta =2.44xx10^(-6)` rad