Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Bicycle lighting wikipedia , lookup
Architectural lighting design wikipedia , lookup
Light pollution wikipedia , lookup
Gravitational lens wikipedia , lookup
Photopolymer wikipedia , lookup
Daylighting wikipedia , lookup
Bioluminescence wikipedia , lookup
Photoelectric effect wikipedia , lookup
Class notes on LIGHT •Light is a type of energy that is composed of 2 things: –An electromagnetic wave –photons Light travels at a speed of 300 000 km/s in a straight line. •Definition: a photon is a particle of light that is derived from energy emitted by an excited electron returning to a lower energy shell. •When light hits an object, 3 things can occur: –Transparent object: light passes through the object and is seen on the other side. –Translucid object: a portion of light goes through the object (other side is not visible). –Opaque object: light does not go through (completely blocked). Visible light corresponds to a series of rays found between red and violet. Beyond red is infrared (invisible) and beyond violet is ultraviolet, also invisible, and can be seen by insects. Reflection: There is a change in the direction of the rays as it meets a surface. Absorption: A portion of light rays can be absorbed by a susbtance while the rest is reflected. (Earth absorbes sunlight and reflects the rest back to space). Refraction: Light rays are bent when passing from one medium to another because of the difference in the light’s speed in each medium. (Medium = air (faster) and water (slower)). White light dispersion •Thin ray of light is projected on a prism: the visible spectrum of white light appears. Different wavelengths of white light are separated and appear on the other side of the prism. •White light is composed of all colors mixed together. Bill Nye video watched in class: http://www.youtube.com/watch?v=gtgBHsSzCPE Videoes not watched in class, but are helpful: Video on dispersion of light: •http://www.youtube.com/watch?v=7Fl0GZsBhGo Video on the electromagnetic spectrum: http://www.youtube.com/watch?v=cfXzwh3KadE