Alison Oswald, age 11, of Salt Lake City, Utah, for her question:

HOW DOES A MAGNIFYING GLASS WORK?

A magnifying glass makes things look larger than they actually are. The glass has a convex lens that is thicker in the middle than it is at its edge. The magnifying power is measured by the number of times larger an object seen through it appears. If a one inch figure appears to be three inches tall in the glass, the glass has a power of three.

The shorter the focal length of a convex lens, the greater its magnifying power will be.