Understanding Convex and Concave Lenses

The video tutorial explains the structures and actions of convex and concave lenses. It describes the shape and function of a convex lens, which converges parallel rays to a principal focus, and defines the focal length. It then covers the concave lens, which diverges parallel rays, and explains how to determine its principal focus and focal length.

What is the typical shape of a convex lens?

How do parallel rays behave when they enter a convex lens?

What is the focal length of a lens?

Describe the characteristic shape of a concave lens.

What is the principal focus of a concave lens?