Question

assertion: lenses with maximum power have minimum focal length.... Reason: power is the reciprocal of its focal length​

Answer 1

Answer:

The resolving power of a microscope is reciprocal of the distance d. An increase in μ (refractive index of the transparent medium between the objects and the objective of the microscope) will produce a greater resolving power. It also increases with decrease in wavelength. While the resolving power of telescope is defined as the reciprocal of the smallest angular separation between two distant objects whose images are distincity separated by the telescope.

δθ=

D

1.22λ

So for higher resolving power telescope should have the objective lens of large diameter (D) and objects is illuminated by light of small wavelength. Thus, in both the case resolving power is increased by taking illumination light of small wavelength.