| Question | Answer |
| Thin lens equation | 1/o + 1/i = 1/f. o = object distance, i = image distance, f = focal length |
| optical fibers | transparent fiber, usually of glass or plastic, that can transmit light down its length by means of total internal reflection |
| critical angle | the minimum angle of incidence for which a light ray is totally reflected within a medium |
| total internal reflection | the 100% reflection (with no transmission) of light that strikes a boundary between 2 media at an angle greater than the critical angle |
| polished surfaces | causes reflection for certain waves |
| monochromatic light | light of a single frequency |
| coherent light | light waves in phase (laser) |
| incoherent light | light waves out of phase |
| diffraction grating | multitude of closely spaced parallel slits that separates light by interference |
| Young's experiment | Monochromatic light through 2 pinholes, creates fringes of darkness and light on screen due to constructive and destructive interference |
| sharp shadows | large object compared to wavelength |
| diffraction | any bending of a wave by means other than reflection or refraction |
| Huygens' Principal | every point on any wave front can be regarded as a new point source of secondary waves |
| 3 useful rays for diverging lens | 1. ray parallel to principal axis bent in same direction as if it came from focal point. 2. through center goes straight. 3. ray headed to focal point on far side bends so emerges parallel |
| 3 useful rays for converging lens | 1. Parallel to principal axis passes through focal point after refraction. 2. ray through center goes straight. 3. ray through focal point in front of lens emerges parallel to principal axis |
| Things required to construct ray diagrams | size and location of object, distance from the center of the lens, focal length. Only have to find 2 rays to find image. |
| real image | formed by converging light rays and that can be displayed on a screen |
| objects behind focal points of converging lenses | inverted, real |
| magnification | image seen through wider angle through lens. Converging lens can only magnify when object is between focal point and lens. image is virtual |
| focal plane | light above and below focal point where light is in focus |
| focal point | point at which rays of light converge where beam of light is parallel to principal axis converges |
| principal axis | line joining centers of curvature |
| focal length | distance between center of the lens and focal point |
| diverging lens | bend rays to diverge as if from single point |
| converging lens | bend rays to converge at single point |
| lens | Piece of glass that has just the right shape, bends parallel rays of light so that they cross and form an image |
| dispersion | separation of light into colors arranged according to frequency |
| mirage | a floating image that appears in the distance and is due to the refraction of light in the earth's atmosphere. Image is the same size and is inverted |
| Snell's law (proves Law of Reflection) | n sin(theta) = n' sin(theta') |
| Index of refraction | Ratio of n of the speed of light in a vacuum / speed of light in a material. (n = c/v) |
| In refraction: when speed increases in the new medium | bends away from normal |
| In refraction: when speed decreases in the new medium | bends towards normal |
| Causes of refraction | changes in speed of light due to different mediums, temperatures or densities |
| wave fronts | diagrams of refraction, lines that represent positions of different crests |
| refraction | the change in direction of a wave as it crosses the boundary between two media in which the wave travels at different speeds |
| What constitutes a rough surface? | wavelength and differences in elevations |
| diffuse reflection | light is incidence on a rough surface and is reflected in many directions |
| images from mirrors | virtual, same size, same distance |
| virtual image | image formed through reflection or refraction that an be seen by an observer but cannot be projected on a screen because light from the object does not actually come into focus |
| reflected ray | ray reflected off medium |
| incident ray | ray that hits medium |
| Law of Reflection | Angle of incidence = angle of reflection |
| % of light reflected off of glass | 4% |
| partially reflected | some energy goes to new medium and some reflected |
| totally reflected | everything reflects |
| reflection | wave reaches a boundary between two media, some or all the wave bounces back into the first medium |
46 cards - created feb 15, 10:37pm