As source of light is at the focus of convex lens. The outcoming light through the lens will be in the form of

Principal focus of convex lens:

Principal focus of convex lens:

Eye gathers light through a lens and image is formed on

How can a convex lens be used to light up a fire?

A ray of light is going towards the focus of a convex lens. Draw a ray digram to show the path of this ray of light after refraction through the lens.

An object is placed at the focus of Convex lens. Where will the image be formed?

Converging light rays are falling on a convex lens. If the focal length of the lens is 30 cm, then find the position of the image.