Physics - Geometrical Optics Question with Solution | TestHub

Resolving power of telescope $=\frac{D}{1.22\lambda }$ Where $D$ is the diameter of the objective lens and $\lambda$ is the wavelength of the light used. With increase in $D$, resolving power of telescope increases. A telescope will have large light gathering power if the diameter of the objective lens is large. Hence a bright image will be form ed by the telescope.