Resolving Power question from MHT CET 2026 (11 Apr, Shift 2)

Answer: (c)

1. Angular separation for just-resolved images $\theta = \dfrac{1.22\lambda}{D}$; in the focal plane $x = f\theta$.
2. $x = \dfrac{1.22\lambda f}{D} = \dfrac{1.22 \times 5000 \times 25}{5}$ Å
3. $x = 30500$ Å
4. So the answer is (c) $30500$ Å.