QQ登录
微博登录 
托福培训
托福考试动态
2017-02-14 14:40
来源：网络
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。
A
Absolute zero
The lowest theoretical temperature a material can have, where the molecules that make up the material have no kinetic energy. Absolute zero is reached at 0 K or –273o C.
Acceleration
A vector quantity defined as the rate of change of the velocity vector with time.
Activity
In radioactive substances, the number of nuclei that decay per second. Activity, A, will be larger in large samples of radioactive material, since there will be more nuclei.
Alpha decay
A form of radioactive decay where a heavy element emits an alpha particle and some energy, thus transforming into a lighter, more stable, element.
Alpha particle
A particle, which consists of two protons and two neutrons. It is identical to the nucleus of a helium atom and is ejected by heavy particles undergoing alpha decay.
Amplitude
In reference to oscillation, amplitude is the maximum displacement of the oscillator from its equilibrium position. Amplitude tells how far an oscillator is swinging back and forth. In periodic motion, amplitude is the maximum displacement in each cycle of a system in periodic motion. The precise definition of amplitude depends on the particular situation: in the case of a stretched string it would be measured in meters, whereas for sound waves it would be measured in units of pressure.
Angle of incidence
When a light ray strikes a surface, the angle of incidence is the angle between the incident ray and the normal.
Angle of reflection
The angle between a reflected ray and the normal.
Angle of refraction
The angle between a refracted ray and the line normal to the surface.
Angular acceleration
A vector quantity, , equal to the rate of change of the angular velocity vector with time. It is typically given in units of rad/s2.
Angular displacement
The net change, , in a point’s angular position, . It is a scalar quantity.
Angular frequency
A frequency, f, defined as the number of revolutions a rigid body makes in a given time interval. It is a scalar quantity commonly denoted in units of Hertz (Hz) or s–1.
Angular momentum
A vector quantity, L, that is the rotational analogue of linear momentum. For a single particle, the angular momentum is the cross product of the particle’s displacement from the axis of rotation and the particle’s linear momentum, . For a rigid body, the angular momentum is a product of the object’s moment of inertia, I, and its angular velocity, .
Angular period
The time, T, required for a rigid body to complete one revolution.
Angular position
The position of an object according to a co-ordinate system measured in s of the angle of the object from a certain origin axis. Conventionally, this origin axis is the positive x-axis.
Angular velocity
A vector quantity, , that reflects the change of angular displacement with time, and is typically given in units of rad/s. To find the direction of the angular velocity vector, take your right hand and curl your fingers along the particle or body’s direction of rotation. Your thumb then points in the direction of the body’s angular velocity.
Antinode
The points midway between nodes on a standing wave, where the oscillations are largest.
Atom
The building blocks of all matter, atoms are made up of a nucleus consisting of protons and neutrons, and a number of electrons that orbit the nucleus. An electrically neutral atom has as many protons as it has electrons.
Atomic number
A number, Z, associated with the number of protons in the nucleus of an atom. Every element can be defined in s of its atomic number, since every atom of a given element has the same number of protons.
Axis of rotation
The line that every particle in the rotating rigid body circles about.
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。
推荐阅读
新东方留学院校库，留学选校有门道
A BETTER YOU,A BIGGER WORLD!
版权及免责声明
①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。
② 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。
③ 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。
托福培训
托福考试动态
