The Law of Reflection usually refers to light; however, one can use the same basic principle in billiards. What The Law of Reflection states is that when an object hits a flat surface coming from a straight line, it will reflect off of the surface at the same angle in which it made contact. One can use this law to predict where the balls will go after being hit against the walls of the billiard table.
The angle at which the object hits the flat surface is called the Angle of Incidence, and the angle at which the object reflects is called the Angle of Reflection. The invisible line that bisects the total angle and which divides it into the Angle of Incidence and the Angle of Reflection is called the Normal.
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