新东方网>留学>SAT考试>SAT辅导>SAT物理>正文

SAT2物理常用术语词汇整理(D)

2011-12-05 18:18

来源:互联网

作者:

  为了方便广大考生更好的复习,新东方网综合整理了SAT2物理常用术语词汇,以供各位考生考试复习参考,希望对考生复习有所帮助。愿大家都能取得好成绩,更多有关留学考试的资讯与辅导资料敬请关注新东方网留学考试频道。

  D

  De Broglie wavelength

  A wavelength, given by = h/mv, which is associated with matter. Louis de Broglie proposed the idea that matter could be treated as waves in 1923 and applied this theory successfully to small particles like electrons.

  Decay constant

  A constant, , not to be confused with wavelength, that defines the speed at which a radioactive element undergoes decay. The greater is, the faster the element decays.

  Decibel

  A logorithmic unit for measuring the volume of sound, which is the square of the amplitude of sound waves.

  Deposition

  The process by which a gas turns directly into a solid because it cannot exist as a liquid at certain pressures.

  Destructive interference

  The cancellation of one wave by another wave that is exactly out of phase with the first. Despite the dramatic name of this phenomenon, nothing is “destroyed” by this interference—the two waves emerge intact once they have passed each other.

  Diffraction

  The bending of light at the corners of objects or as it passes through narrow slits or apertures.

  Diffraction grating

  A sheet, film, or screen with a pattern of equally spaced slits. Typically the width of the slits and space between them is chosen to generate a particular diffraction pattern.

  Direction

  The property of a vector that distinguishes it from a scalar: while scalars have only a magnitude, vectors have both a magnitude and a direction. When graphing vectors in the xy-coordinate space, direction is usually given by the angle measured counterclockwise from the x-axis to the vector.

  Directly proportional

  Two quantities are directly proportional if an increase in one results in a proportional increase in the other, and a decrease in one results in a proportional decrease in the other. In a formula defining a certain quantity, those quantities to which it's directly proportional will appear in the numerator.

  Dispersion

  The separation of different color light via refraction.

  Displacement

  A vector quantity, commonly denoted by the vector s, which reflects an object’s change in spatial position. The displacement vector points from the object’s starting position to the object’s current position in space. If an object is moved from point A to point B in space along path AB, the magnitude of the object’s displacement is the separation of points A and B. Note that the path an object takes to get from point A to point B does not figure when deining displacement.

  Distance

  A scalar quantity. If an object is moved from point A to point B in space along path AB, the distance that the object has traveled is the length of the path AB. Distance is to be contrasted with displacement, which is simply a measure of the distance between points A and B, and doesn’t take into account the path followed between A and B.

  Doppler shift

  Waves produced by a source that is moving with respect to the observer will seem to have a higher frequency and smaller wavelength if the motion is towards the observer, and a lower frequency and longer wavelength if the motion is away from the observer. The speed of the waves is independent of the motion of the source.

  Dot product

  A form of vector multiplication, where two vectors are multiplied to produce a scalar. The dot product of two vectors, A and B, is expressed by the equation A · B = AB cos .

  Dynamics

  The application of kinematics to understand why objects move the way they do. More precisely, dynamics is the study of how forces cause motio

  小编提醒:单词的记忆要靠长期的坚持,考生们一定要持之以恒,每天都拿出来看一看背一背,让这些词汇在大脑中形成长期记忆,这样就不会轻易地忘记背过的词汇了。

  相关推荐》》》北美留学高峰论坛

  更多SAT考试信息》》》新东方网SAT频道

(责任编辑:张梦璇)

新东方网托福官方微信:新东方托福 (微信号:xdftoefl

最新考试资讯、托福预测、托福解析,请扫一扫二维码,关注我们的官方微信! 

新东方SAT辅导专区

班级名称 上课地点 上课时间 费用 详细

焦点推荐

版权及免责声明

凡本网注明"稿件来源:新东方"的所有文字、图片和音视频稿件,版权均属新东方教育科技集团(含本网和新东方网) 所有,任何媒体、网站或个人未经本网协议授权不得转载、链接、转贴或以其他任何方式复制、发表。已经本网协议授权的媒体、网站,在下载使用时必须注明"稿件来源:新东方",违者本网将依法追究法律责任。

本网未注明"稿件来源:新东方"的文/图等稿件均为转载稿,本网转载仅基于传递更多信息之目的,并不意味着赞同转载稿的观点或证实其内容的真实性。如其他媒体、网站或个人从本网下载使用,必须保留本网注明的"稿件来源",并自负版权等法律责任。如擅自篡改为"稿件来源:新东方",本网将依法追究法律责任。

如本网转载稿涉及版权等问题,请作者见稿后在两周内速来电与新东方网联系,电话:010-60908555。