Know the terms refraction, reflection and absorption as they refer to the movement of light waves

Three cases happen when a light wave strikes an object. Light waves can either be: absorbed, reflected or refracted. The differences are as follows:

a. Absorption - light stops at the object causing it to appear dark or opaque.
b. Reflection - this could happen either in a smooth or rough surface. On a smooth surface, for example mirror or glass, light bounces off the surface at angle equal to the incoming light wave. On a rough surface e.g. earth, light bounces at many angles because the surface is uneven.
c. Refraction - light goes through the object and bends at an angle. Typical thing you see when diamond  or water is struck by light. 

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