Why should the objective lens of a compound microscope have small focal length?

Answer the following questions: Why must both the objective and the eyepiece of a compound microscope have short focal lengths?

Define the magnifying power of a compound microscope when the final image is formed at infinity. Why must both the objective and the eye piece of a compound microscope has short focal length? Explain.

The focal lengths of the objective and eye-piece of a compound microscope are 4 cm and 6 cm respectively. If an object is placed at a distance of 6 cm from the objective, what is the magnification produced by the microscope? Distance of distinct vision = 25 cm.

The focal lengths of the objective and eye-piece of a compound microscope are 1.25 cm and 5 cm respectively. Find the position of the object relative to the objective in order to obtain an angular magnification of 30 in normal adjustment.

The focal length of the objective of a microscope is

Explain with reasons,how the resolving power of a compound microscope will change when aperture of the objective lens is increased.

How does the resolving power of a compound microscope get affected on increasing the focal length of its objective?