Question

If we hold a convex lens over a sheet of paper in sunlight such that there is tiny spot of light on the paper for a while. What happens? Why?

Answer 1

1. If a convex lens is held over a paper in sunlight such that there is a tiny spot of light on the paper for a while the paper bums.

2. This is due to the heat energy of the sun concentrated at a point due to the convex lens.