| A | B |
|---|
| radio waves | low-frequency waves widely used for communication |
| gamma rays | the most powerful and penetrating form of electromagnetic radiation |
| microwaves | waves commonly used for radar, satellite communications, and heating food |
| x-rays | high-frequency electromagnetic waves used in medicine, dentistry, and airport security to see inside objects |
| visible light | electromagnetic waves that our eyes can perceive |
| ultraviolet rays | electromagnetic waves responsible for tanning and sunburn |
| infrared waves | electromagnetic waves sometimes referred to as heat waves |
| particle theory of light | states that light can be pictured as streams of tiny particles emitted by light sources |
| time dilation | apparent slowing down of time (from perspective of observer) for an object traveling at near-light speed |
| white | perceived as a combination of all the colors of light mixed together |
| theory of relativity | all motion is relative to some reference point and that the speed of light is constant in relation to any observer |
| black | perceived as absence of all colors |
| electromagnetic spectrum | arrangement of all forms of electromagnetic radiation in order of frequency and wavelength |
| lens | a piece of glass or other substance specifically designed to refract light |
| vacuum | the speed of light in a ____ is always constant |
| billionth of a meter | A nanometer |
| ROYGBV (six colors of visible spectrum) | red, orange, yellow, green, blue, violet |
| Isaac Newton | English guy who discovered that white light is a combo of other colors; wrote Optiks |
| Aristotle | Greek guy who taught that pure white light contains no color |
| Theodore Maiman | American who constructed the first laser |
| Christian Huygens | Dutch scientist who first proposed the wave theory of light |
| Einstein | Jewisth scientist who predicted stimulated emission and formulated the theory of relativity |
| Wilhelm Roentgen | German scientist who discovered X-rays |
| James Clerk Maxwell | Scottish scientist who discovered that light consists of electromagnetic waves |
| Heinrich Hertz | German who first studied radio waves in the laboratory |
| Max Planck | German scientist who showed that the energy of an electromagnetic wave is directly related to the wave's frequency |
| speed of light in vacuum | fastest possible speed in universe |
| laser | light amplification by stimulated emission of radiation |
| particles | light acts more like______ when interacting with matter |
| mirage | illusion of water covering a hot highway in the distance |
| quantum | theory of light states that light has characteristics of both particles and waves |
| concave | lens that is thinner in the middle than at the edges, causing light rays to be spread out and objects appear smaller |
| 300,000km/s | speed of light in a vacuum |
| convex | lens that is thicker in the middle than the edges, causing light rays to be concentrated and objects to appear magnified |
| red | color witht the lowest frequency |
| cyan, magenta, yellow | subtractive primary colors of pigment |
| violet | color of visible light witht he highest frequency |
| red, green, blue | additive primary colors |
| iridescence | array of many colors casued by the interference of light waves (seen on the surface of soap bubbles) |
| photons | tiny bundles or packets of energy |
| c | speed of light |
| reflection | bouncy of light rays off a surface so that htey continue in a different direction |
| rainbow | visible spectrum produced in the sky by falling raindrops |
| diffraction | spreading out of light waves as a result of passing through a narrow gap |
| refraction | the bending of light rays when they cross a boundary between two mediums |
| interference | mutual reinforcement or cancellation of two light waves |
| hologram | three-dimensional image produced by laser light |
| fiber optics | technique of transmitting light through narrow glasslike wires, such as for communications |
| coherent, intense, polarized | properties of laser light |
| polarized | beam of light containing waves that all vibrate in teh same direction |
| radar | device that used reflected electromagnetic waves to measure the distance and direction of objects |
| UVB | type of UV radiation that causes suntans and sunburns |
| stimulated emission | process that occurs when an excited atom is struck by one photon and emits two photons |
| monochromatic | light that consists of only one frequency |
| coherent | light in which all the waves are in step |
