How can you burn something with a glass and sun???

Question

How can you burn something with a glass and sun???

Answer 1

If the glass happens to be a lens, which focuses / concentrates the sun's energy into a small area, then the heat produced can be enough to burn.

Answer 2

Yes. You need a concave lense and a flamable material such as a piece of paper. You concentrate the suns rays at one point and a fire may start.

Answer 3

Since this is a science question, get a magnifying glass and go outside and experiment on a blade of grass or some wood.  You just have to adjust the distance of the glass from the object until you focus the light to a very fine pinpoint.  Have fun.