- Take a small piece of thin foam or rubber.
- Put some pins in a straight line on the foam.
- All these pins are perpendicular to the foam.
- If the foam was considered as a mirror, each pin would represent the normal at the point.
- Any ray incident at the point where the pin makes contact with the surface will reflect at the same angle the incident ray made with the pin - normal.
- Now bend the foam piece inwards.
- The pins still represent the normal at various points.
- You will observe that all the pins tend to coverage at a point.
- This will be appear like a concave mirror.
- Now bend the foam piece outwards.
- The pins seem to move away from each other that means they diverge.
- The pins still represent the normal at various points.
- This will be appear like a convex mirror.
