Reflection-the change in direction of a wave at a surface that causes it to bounce away from the surface
Angle of incidence-the angle between a ray that strikes a surface and the line perpendicular to that surface at the point of contact
Angle of reflection-the angle formed by the line perpendicular to a surface and the direction in which a reflection ray moves
Virtual image-an image formed when light rays diverge that cannot be projected on a screen
Real image-an image formed by the intersection of light rays that can be projected on a screen
Concave mirror-a mirror whose reflecting surface is the segment of the inside of a sphere
Convex mirror-a mirror whose reflecting surface is an outward-curved segment of a sphere
Refraction-the bending of a wave as the wave passes between two substances, resulting in a change of speed of the wave
Index of refraction-the ratio of the speed of light in a vacuum to the speed of light in that substance
Lens-A transparent object that refracts light rays to create images
Total internal reflection-the complete reflection that takes place within a substance when the angle of incidence of light striking the surface is greater than the critical angle
Ray diagram-diagrams used to show the path of light rays to form an image
Focal point-the point at which rays meet to form an image
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