Light is known to behave in a very how to draw a water ripple manner. If a ray of light could be observed approaching and reflecting off of a flat mirror, then the behavior of the light as it reflects would follow a predictable law known as the law of reflection. The diagram below illustrates the law of reflection. Reflection and the Locating of Images It is common to observe this law at work in a Physics lab such as the one described in the previous part of Lesson 1.
To view an image of a pencil in a mirror, you must sight along a line at the image location. As you sight at the image, light travels to your eye along the path shown in the diagram below. It just so happens that the light that travels along the line of sight to your eye follows the law of reflection. For example, in Diagram A above, the eye is sighting along a line at a position above the actual image location.
For light from the object to reflect off the mirror and travel to the eye, the light would have to reflect in such a way that the angle of incidence is less than the angle of reflection. In Diagram B above, the eye is sighting along a line at a position below the actual image location. Consider the diagram at the right. Which one of the angles is the angle of reflection? A ray of light is incident towards a plane mirror at an angle of 30-degrees with the mirror surface.