Question

how is the resolving power (RP) of a microscope affected, when the (a) wavelength of illuminating radiation decreases and (b) diameter of the objective lens decreases ?

Answer 1

resolving power = 1/ dmin = 2 U sinbeta/ 1.22 (lamda)
(i) Where lamda is a wavelength. So, if wavelength of illuminating radiation is decreased then resolving power increases.
(ii) On decreasing diameter , beta decreases so resolving power as well decreases.