Assume that light of wavelength 600nm is coming from a star. The...

Limit of resolution of a telescope is given by,

{ϑ}_\min = \dfrac{1 . 22\lambda}{a}, where $\lambda$ is the wavelength of the light and $a$ is the aperture diameter.

Given, $\lambda = 600nm\text{and}a = 2m$

{ϑ}_\min = \dfrac{1 . 22 \times 6 \times {10}^{- 7}}{2}

⇒ {ϑ}_\min = 3 . 66 \times {10}^{- 7}rad