Assume that light of wavelength `6000 Å` is coming from a star. What is the limit of resolution of a telescope whose objective has a diameter of 100 inch ?

Explanation

A 100 inch telescope implies that
a = 100 inch = 254 cm . Thus if ,
`lambda ~~ 6000 Å = 6 xx 10^(-5) ` cm then ,
`Delta theta = (1.22lambda)/(a) ~~ 2 . 9 xx 10^(-7)` radians