Question

Explain why a short focal legth lens is used as the objective lens in a microscope?

Answer 1

SOlution:

The objective lens is the lens which is closer to the object (sample) and is at the bottom. This is of very short focal length because the light has to be brought to focus inside the microscope tube. Whenever the objective is of short focal length , the object will be brought within the focal lelngth of the objective and thus gives a highly magnified image of the object.

A simple microscope uses a bi convex lens. Its property is that when an object is adjusted to be within its focal length , it produces a very large magnified , upright image . So microscope uses this type of lens , since the purpose of a microscope is to enlarge the saples or objects.