Lynda Wallace, age 13, of Victoria, r C., for her question:

Can a magnifying glass make the sun hotter?

The magnifier is a little dome of glass. The sunbeams, coming down from the sun in straight lines, strike this glassy dome at various angles. The curved surface bends these rays inwards, The rays are pointed from the large outer surface of the curve to a smaller area, In this way they are concentrated or focused on a smaller area.

Sunbeams coming down straight from the sun are not hot enough to burn a sheet of paper. But when a number of these rays are gathered together, they become hotter. This happens when they are slanted together, or focused through a magnifying glass. On a sunny day, a magnifying glass held over a sheet of paper may focus enough heat to start a fire.