Curved Mirrors

Concave and convex

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• Concave mirrors focus at $f = R/2$; convex mirrors spread light.
• Mirror equation: $\frac1{d_o} + \frac1{d_i} = \frac1f$, magnification $-\frac{d_i}{d_o}$.
• Inside f a concave mirror magnifies; convex mirrors always shrink.

Steps

1. Focusing by reflection
2. Focal length
3. A shaving mirror
4. Headlights and dishes
5. A security mirror
6. Closer than they appear