Question

How is image formed by Convex Lens?

Answer 1

Hint: An optical lens is made up of two spherical surfaces in most cases. The lens is called a convex lens when those surfaces are bent outwards. These lenses will converge and concentrate a beam of light coming from the outside to a point on the other side. The focus is this point, and the focal length of a convex lens is the distance between the lens's center and the focus.

Complete step by step solution:
The image formed by a convex lens is real and is very small, since there are many ways of forming an image by a lens, so we will be discussing only the basic one in which the object is placed at infinity and the image is formed at focus which is of point size.
The figure below is the ray diagram for formation of image by a convex lens

In the figure, we can see that we have placed a candle at infinity and the incident rays are coming towards the lens from the infinity. Incident rays are those which are on the left side of the lens. The point “F” is the focal point of the lens and the Point “O” is the optical center. The line joining all the points including “F”, “2F” and “O” is called the principal axis
Hence, we can say that when an object is placed at infinity, a real image is formed by a convex lens which is of very small size.
Note: Spherical lenses are made by combining two spherical transparent surfaces. There are two types of spherical lenses in general. Convex lenses are made by joining two spherical surfaces that bulge outward, while concave lenses are made by joining two spherical surfaces that curve inward.