Question

The resolving power of a compound microscope will increase with

• A. Decrease in wave length of light and increase in numerical aperture.
• B. Increase in wave length of light and decrease in numerical aperture.
• C. Increase in both wave length of light and numerical aperture.
• D. Decrease in both wave length of light and numerical aperture.

Answer 1

Answer: (A)

Decrease in wave length of light and increase in numerical aperture.

Resolving power is the ability to distinguish two close objects as distinct. It is calculated by the formula 0.61 wavelength/ numerical aperture, where numerical aperture is the light collecting ability of lens. It is clear that resolving power will be more if wavelength is less and numerical aperture is more. Thus, the correct answer is option A.