What is the focal length of the mirror?
1 answer(s)
The focal length is about the mirror's focusing power. It's the distance from the mirror to the point where light focuses. For a curved mirror, you can find it easy. Just measure the radius of the curve, like the distance to the center of the sphere it came from. The focal length is exactly half of that distance. So, a mirror with a 20 cm radius has a 10 cm focal length. Every mirror is different, depending on its curve.