Experiment 4

Reflection Laws

Materials:

·        A plane 8 cm x 5 cm mirror

·        3 pencils

Procedure

1. Place the first pencil (let us call it pencil “A”) in front of the mirror and observe the image that is formed behind the mirror.
2. Stay to the left of pencil A and place pencils B and C so that they are aligned with the image of pencil A.  (You may have to bend down so that your eye is at the surface of the table you are working on)
3. Mark the position of the reflected rays that go through B and C with a line.  Call “O”, the point in the mirror where the reflected ray comes from.
4. Trace the ray incident from A to the point O of the mirror
5. Trace the normal line to the mirror in the point O and measure the angles formed by the incident ray and the normal line.  Measure the angle between the reflected ray and the normal line.

1. What are the measurements of each angle?
2. Does the law of reflection hold true?

c.      Repeat this experiment watching the mirror on the right side of the pencil.