Assume that light of wavelength 500 nm is used to illuminate a telescope. What is the resolving power of a telescope whose objective has a radius of 200 cm ?

Explanation

Limit of resolution `Delta theta=(0.61 lamda)/a`
`Delta theta=(0.61 times 500 times 10^-9)/(200 times 10^-2)`
`Delta theta approx 1.525 times 10^-7`
R.P.= `1/(Delta theta) approx 6.5 times 10^6`