Question

When is spherical lens is held toward sun and a sharp image is formed on a piece of black paper,a hole get burnt in the black paper, after sometime

What is the relative advantage of using a black paper rather than a white paper

Answer 1

Answer:

The rays coming through the sun to convex lens is said to infinite and the distance from lens to paper is it's Focal length. As per the question a sharp image of sun is formed on the paper, thus the image must be very small compared to the object which is situated at infinity compared to other parameters.