Why does the eye-lens not have to do all the work of converging incoming light rays ?

What is meant by converging of light rays?

Why do the albinos have pink eyes ?

Why does the objective lens of an astronomical telescope have a large light gathering power?

List the important factor on which the ability of a lens to converge or diverge light rays depends on ?

What is the nature of the eye lens and what does the eye lens do ?

Explain why a convex lens is called a converging lens.

Some rays falling on a converging lens are focussed 20 cm from the lens. When a diverging lens is placed in contact with the converging lens, the rays are focussed 30 cm from the combination. What is the focal length of the diverging lens?