Q 12-10-140JEE MainJEE Main 2019 (8 Apr, Shift 2)Easy
Calculate the limit of resolution of a telescope objective having a diameter of $200\ \text{cm}$, if it has to detect light of wavelength $500\ \text{nm}$ coming from a star.
Answer: (A) $305\times10^{-9}$ radian
$$\Delta\theta = \frac{1.22\lambda}{D} = \frac{1.22\times500\times10^{-9}}{2} = 305\times10^{-9}\ \text{rad}$$
Solution by Sreeraj P, M.Sc Physics