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PS Chapter 22: Light
PS Chapter 22: Light Coach Leach
Term | Definition |
---|---|
Luminous Object | An object that is producing visible light. |
Illuminated Object | An object that is visible because it reflects light from an external source. |
Ray | A model of light in which the endpoint represents the light's source and the light travels in one direction. |
Transparent Material | A material through which light passes without scattering, transmitting a clear image. |
Translucent Material | A material through which light passes but the light is scattered and does not transmit a clear image. |
Opaque Material | A material through which visible light cannot pass. |
Primary Color | One of the three colors of visible light that the human eye can sense; mixed to produce other colors. |
Secondary Color | A color of light that is produced when primary colors are mixed. |
Subtractive Color | A color that forms because of pigments absorbing some wavelengths of light that strike an object. |
Additive Color | A color that is produced by combining the wavelengths of different colors. |
Diffuse Reflection | The reflection off a rough or uneven surface that reflects light rays in all directions. |
Specular Reflection | Reflection that occurs when a smooth surface reflects light rays in mostly the same direction which is mirrorlike, reflecting all rays and wavelengths uniformly. |
Incident ray | A light ray approaching a surface; an incoming ray. |
Reflected Ray | The ray that bounces off a surface. |
Law of Reflection | The law that states that when a light ray reflects off a surface, the angle of the incident ray equals the angle of the reflected ray. |
Plane Mirror | A flat mirror. |
Virtual Image | An image produced by diverging rays, formed at the point from which the diverging rays would have originated; cannot be projected. |
Real Image | An image that forms at the point where converging rays of light intersect. |
Concave Mirror | A curved mirror with the reflective side on the inside of the curve. |
Focal Point | The point on an optical axis at which all reflected or refracted light rays from incident rays that are parallel to the optical axis converge. |
Focal Length | The distance from the center of a lens or mirror to its focal point. |
Convex Mirror | A curved mirror with the reflective side on the outside of the curve. |
Index of Refraction | The ratio of the speed of light in a vacuum to the speed of light in the medium. |
Total Internal Reflection | When a ray of light can't pass from one medium to another; instead, the ray reflects off the boundary between the two media and remains within the first medium. |
Lens | A disk of transparent material that refracts light to produce a real or virtual image. |
Converging Lens | A lens that causes light rays to come together; also known as a convex lens. |
Diverging Lens | A lens that causes light rays to separate; also know as a concave lens. |