The Law of Reflection Light is reflected from a plain mirror. This experiment is designed to investigate, how light is reflected. Diagram: Place a mirror along the flat edge of the protractor. Using the ray box, shine a ray of light at the centre, this is the incident ray. The angle between this ray and the normal (90°) is the angle of incidence. The ray is reflected by the mirror. The angle between the normal and the reflected ray is called the angle of reflection. Measure the angle of incidence and the angle of reflection. Results: Angle of Incidence (i) Conclusion: Angle of Reflection (r) Curved Mirrors A flat or plain mirror reflects light according to the Law of Reflection. What about curved mirrors? A mirror that curves inwards is called a concave mirror. A mirror that curves outwards is called a convex mirror. Using the ray box and the grating with three slits, draw what happens as the three light rays shine on the curved mirrors. 1. Have you seen this effect before? 2. Where might mirrors of each type be used?