Question

E.
Long Answer Questions:
* With the help of a ray diagram, explain the following terms:
(a) Focus of a convex lens (b) Optical centre of a convex lens (c) Focal length of a convex lens
hieman huden​

Answer 1

Answer:

a) Focus of a Convex lens

When the incident light ray is parallel to principal axis and after refraction it converge at a point on principal axis . That point is know as principal focus of Convex lens.

b) Optical Centre of a convex lens

The point inside a convex lens through which light ray passes without changing it's direction or path are called as Optical Centre of Convex lens.

c) Focal length of a convex lens

The distance between principal focus and optical center of the convex lens are called Focal length of a convex lens. And Focal length of convex lens is always positive.