力学专业英语考试重点整理.doc

力学专业英语考试重点整理1、 单词：英译汉、汉译英8Centroid 质心，形心Elasticity 弹力，弹性Linear 线性的，直线的Prismatic 棱镜的，棱柱形的Strain 应变Stress 应力Tension 张力，拉力，拉紧Alloy 合金Aluminium 铝Ductile 易延展的，韧性的Failure 失败，破坏，失效Lateral 侧面的，横向的Necking 颈缩Couple 力偶Cylinder 圆筒，圆筒状物Inertia 惯性，惯量，惰性Shaft 轴，杆状物Torsion 扭矩Cantilever 悬臂梁，伸臂Neutral 中性的Statics 静力学，静止状态，静态Symmetry 对称Transverse 横向的，横断的Astronomer 天文学家Galaxy 天河，银河，星系Planet 行星Collinear 共线的，在同一直线上的Dimension 尺寸，大小，维数Equate 使相等，等同Parameter 参量，参数Visualize 想象，形象化，使看得见Acceleration 加速度Dynamics 动力学Stationary 不动的，稳定的，定常的Vector 矢量Velocity 速度Angular 角的，角度的Coordinate 坐标Radian 弧度Shaft 轴Symbol 符号Conservation 守恒，保存Differentiation 微分Integration 积分，集成，一体化Interval 间隔，间隙，空隙Linear 直线的，线性的，一次的Moment 力矩，瞬间，片刻Vector 矢量Velocity 速度Derivative 导数，派生的Frequency 频率Friction 摩擦Magnitude 大小，量级Power 力量，乘方，幂Viscous 黏性的Continuum 连续体，连续统Rectangular 矩形的，成直角的Resultant 合成的，合力，合量Torque 扭转力，扭矩Dilatation 膨胀，扩张Distortion 扭曲，变形Isotropic 各向同性的Tensor 张量Coordinate 坐标Crack 裂缝Curvature 曲率Ellipse 椭圆Formula 公式Function 函数，功能Buckle 屈曲，皱曲，弄弯，翘曲Deflection 挠曲，偏向Wrinkle 皱纹，皱褶，起皱Factor 因数，系数Flexural 弯曲的，挠曲的Notch 缺口，凹槽，刻痕Vibrate 振动（v）Vibration 振动（n）Detector 发现者，侦察器，探测器，检波器Vacuum 真空，空间，真空的，产生真空的Other than 除了2、 句子：英译汉1、 The concepts of stress and strain can be illustrated in an elementary way by considering the extension of a prismatic bar. As shown in Fig. 1, a prismatic bar is one that has constant cross section throughout its length and a straight axis. In this illustration the bar is assumed to be loaded at its ends by axial forces P that produce a uniform stretching, or tension, of the bar.翻译：应力和应变的概念可以通过考虑一个棱柱形杆的拉伸这样一个简单的方式来说明。一个棱柱形的杆是一个遍及它的长度方向和直轴都是恒定的横截面。在这个实例中，假设在杆的两端施加有轴向力F，并且在杆上产生了均匀的伸长或者拉紧。2、 By making an artificial cut (section mm) through the bar at right angles to its axis, we can isolate part of the bar as a free body see Fig. 1(b). At the left-hand end the tensile force P is applied, and at the other end there are forces representing the action of the removed portion of the bar upon the part that remains. These forces will be continuously distributed over the cross section, analogous to the continuous distribution of hydrostatic pressure over a submerged surface.翻译：通过在杆上人工分割出一个垂直于其轴的截面mm，我们可以分离出杆的部分作为自由体【如图1(b)】。在左端施加有拉力P，在另一个端有一个代表杆上被移除部分作用在仍然保存的那部分的力。这些力是连续分布在横截面的，类似于静水压力在被淹没表面的连续分布。3、 We are so used to our life on the surface of the earth that it can be quite an effort for our minds to break free of all the ideas that we take for granted. We talk about up and down , but we know that what is down for us is up for someone else on the other side of the world. We can feel that things are heavy, and we often think of weight as being a fixed quality in an object, but it is not really fixed at all. If you could take a one-pound packet of butter 4,000 miles out from the earth, it would weigh only a quarter of a pound.翻译：我们是如此熟悉在地球表面上的生活，以至于需要很努力才能从心理打破我们认为理所当然的观点。我们谈论“上”和“下”，但是我们知道对于我们来说是“上”，对于世界另一边的人来说就是“下”。我们可以感受到物体很重，并且我们经常认为“重量”是物体固定的量，但是它不总是固定的。如果你把一包一磅重的黄油带到离地球4000英里的地方，它将只有磅。4、 Why would things weigh only a quarter as much as they do at the surface of the earth if we took them 4,000 miles out into space? The reason is this : all objects have a natural attraction for all other objects, this is called gravitational attraction. But the power of attraction between tow objects gets weaker as they get farther apart.翻译：为什么我们把物体带到空中4000英里处，它的重量只有地表时的？理由是：所有的物体对于其他的物体都有自然的吸引力，这叫做万有引力。但是两个物理间吸引的程度会随着他们愈来愈远，变的愈来愈弱。5、 What about the weight of our one-pound packet of butter on the surface of the moon? On the moon there will be an attraction between the butter and the moon, but the butter will weigh only about one sixth as much as it does on the earth. This is because the moon is so much smaller than the earth. The amount of gravitational pull that a body produces depends on the amount of material in it. So this is one of the first things we need to remember: that the weight of an object in space is not the same as its weight on the surface of the earth.翻译：一包一磅重的黄油在月球上的重量又是多少呢？在月球上，黄油和月球之间有吸引力，但是黄油只有地球上重量的。这是因为月球比地球小的多。物体产生的引力值取决于它自身材料的数量。因此这是我们首先需要记住的事情：物体在太空中的重量与在地球表面的重量是不同的。6、 When a medium is disturbed by the passage of a wave through it, the particles comprising the medium are caused to vibrate. To take a simple example, corks floating on the surface of a pond will bob up and down owing to the influence of water waves. The bob of a simple pendulum and the weight hanging freely from the end of a spring are other examples of particles which may be set in vibration, and most readers will have a good mental picture of these vibrate.翻译：当介质由于波通过它而引起扰动时，由介质组成的质点发生振动。举一个简单的例子，漂浮在池塘表面的软木塞由于水波的影响上下跳动。简单钟摆的浮子和自由悬挂在弹簧末端的重量，是可能处于振动中的质点的其他例子，多数读者将会对这些质点如何振动有一个好的印象。7、 The motion of a vibrating particle is periodic, that is, after equal intervals of time(the period T) the system finds itself in exactly the same situation. The bob of the pendulum, for example, is found to be at the same position, moving with the same velocity and acceleration as it was T seconds earlier, and these quantities will be the same T, 2T , 3T, etc. Seconds later. During the interval of one period, a vibrating system is said to go through a cycle of situation, and the frequency (f) is defined as the number of cycles occurring in one second. Clearly, then ,f=1/T, the dimension of f is second-1 . This unit is termed the hertz.翻译：一个振动质点的运动时周期性的额，也就是说，在相等的时间间隔（时段T）后，系统将会准确的处于相同的位置。例如，将会发现钟摆的浮子处于相同的位置，以跟T时刻前相同的速度和加速度移动，这些量在T，2T，3T等时刻后也是一样的。在一个时间间隔内，振动系统据说经历了一个周期的状态，频率（f）被定义为在一秒内发生循环的次数。很明显，f=，f的单位是。这个单位被叫做赫兹（Hz）。8、 The simplest kind of periodic motion is that experienced by a point, moving along a straight line, whose acceleration is directed towards a fixed point on the line and is proportional to its distance from the fixed point. This is called simple harmonic motion（s.h.m.）. Suppose a point P moves along a straight line so that its position with respect to a fixed point o is completely specified by the single coordinate x. The acceleration of the moving point is d2x/dt2 ,which is directed towards the point o and proportional to he distance x. Thus where is a positive constant. 翻译：最简单的一类周期运动时，一个支点沿着直线运动，它的加速度指向线的一个固定点，并且与从固定点起计算的距离成比例。这叫做简谐运动。假设一点P沿着一直线移动，以便它的关于点沿着一直线移动，以便它的关于点O的位置完全由位移的坐标X指定。移动点的加速度是，指向O，并且与距离X成比例。这样得到，式中是正常数。9、 If the equations of equilibrium and compatibility are examined, it is found that the equations which involve stresses involve only stresses, body forces, and accelerations, but do not involve strains or displacements. Furthermore, those equations which involve strains and displacements do not contain stresses.翻译：如果观察平衡方程和相容方程，就会发现包含应力的方程只包含应力、体力和加速度，但是不包含应变和位移。另外，那些包含应变和位移的方程不包含应力。10、 Since the application of forces to a body produces both stress and deformation, it is expected that the stresses on an element can be related to the deformation which these stresses produce. Such a set of relationships will then complete the description of the action of loads on the body. Experience has demonstrated that these relationships will depend on the material in question.翻译：由于作用于物体上的力使物体产生应力和变形，人们可以看到单元上的应力与这些应力产生的变形有关。这样一组关系完成了对作用在物体上荷载的描述。实验表明这些关系取决于所讨论问题的材料。11、 For most engineering materials, elastic strains are always sufficiently small that the relationship between the stress and strains is linear. The most general set of linear rel