机械工程专业英语教程 （第5版）全套PPT课件.pptx

Lesson 1 Basic Concepts in Mechanics TerminologyText tour 《机械工程专业英语教程》Terminologymechanics1. The branch of physics that is concerned with the analysis of the action of forces on matter or material systems.力学：物理学的一个分支，研究分析力对物体或物质系统的作用2. Design, construction, and use of machinery or mechanical structures.机械学：机械或机械结构的设计、制造和使用《机械工程专业英语教程》Gear 齿轮 A toothed machine part, that meshes with another toothed part to transmit motion or to change speed or direction. 齿轮：有齿的机器零件，与另一个有齿零件相啮合，从而传递运动或者改变运动的速度或方向。 From Wikipedia, the free encyclopedia Meshing gears transmitting rotational motion 《机械工程专业英语教程》Journal bearing 滑动轴承V belt and pulleyV带和带轮Bearing A device that supports, guides, and reduces the friction of motion between fixed and moving machine parts.轴承：在机器的固定和运动部件之间起支承、引导和减少运动摩擦作用的装置。《机械工程专业英语教程》 Animation of a rigid ball and deformable body (exaggerated)刚性球与变形体的动画演示 (夸大的表示方法）《机械工程专业英语教程》 Scalar A quantity, such as mass, length, or speed, that is completely specified by its magnitude and has no direction. 标量：一个只有大小没有方向的量，如质量、长度或速率等Velocity is defined as the rate of change of position with respect to time.速度 被定义为位置对时间的变化率。Acceleration is defined as the rate of change of velocity with respect to time.加速度 被定义为速度对时间的变化率。Momentum A measure of the motion of a body equal to the product of its mass and velocity动量：表示物体运动特性的一个物理量，等于运动物体的质量和速度的乘积。《机械工程专业英语教程》Text tourThe branch of scientific analysis which deals with motions, time, and forces is called mechanics and is made up of two parts, statics and dynamics. Statics deals with the analysis of stationary systems, i.e., those in which time is not a factor, and dynamics deals with systems which change with time.对运动、时间和作用力做出科学分析的分支称为力学。它由静力学和动力学两部分组成。静力学是对静止系统进行分析，即在其中不考虑时间这个因素，动力学则是对随时间而变化的系统进行分析。《机械工程专业英语教程》Forces are transmitted into machine members through mating surfaces, e. g., from a gear to a shaft or from one gear through meshing teeth to another gear (see Fig. 1.1) , from a V-belt to a pulley, or