Question

Resolving power of telescope increases when

• A. wavelength of light decreases
• B. wavelength of light increasing
• C. focal length of eye-piece increases
• D. focal length of eye-piece decreases

Answer 1

The correct option is A wavelength of light decreases

Resolving power of telescope RP$=\frac{a}{1.22\lambda }$

where $a$ is the diameter of objective lens and $\lambda$ is the wavelength of light.

$⟹$ RP $\propto \frac{1}{\lambda }$

Thus resolving power of telescope increases when wavelength of light is decreased.