Q 12-10-142JEE MainJEE Main 2019 (9 Apr, Shift 2)Easy
Diameter of the objective lens of a telescope is $250\ \text{cm}$. For light of wavelength $600\ \text{nm}$ coming from a distant object, the limit of resolution of the telescope is close to
Answer: (B) $3.0\times10^{-7}\ \text{rad}$
$$\Delta\theta = \frac{1.22\lambda}{D} = \frac{1.22\times600\times10^{-9}}{2.5} \approx 2.9\times10^{-7}\ \text{rad} \approx 3.0\times10^{-7}\ \text{rad}$$
Solution by Sreeraj P, M.Sc Physics