英语翻译把以下文章翻译成英语,公式可略As an illustration of the magnitude of the fluctuations involved,atmospheric pressure is normally 1.012 x 10 5 N/m 2 at sea level; a barely audible signal might fluctuate as little as 10 5 N/m 2
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英语翻译把以下文章翻译成英语,公式可略As an illustration of the magnitude of the fluctuations involved,atmospheric pressure is normally 1.012 x 10 5 N/m 2 at sea level; a barely audible signal might fluctuate as little as 10 5 N/m 2
英语翻译
把以下文章翻译成英语,公式可略
As an illustration of the magnitude of the fluctuations involved,atmospheric pressure is normally 1.012 x 10 5 N/m 2 at sea level; a barely audible signal might fluctuate as little as 10 5 N/m 2 from this value,and a painfully loud continuous noise only about 10 N/m 2,that is,only 0.01°70 of the atmospheric value.(The unit of newtons per square meter,N/m 2,is sometimes replaced by its equivalent,the pascal,Pa.)
2.1 SIMPLE WAVE NATURE OF SOUND
2.1.1 Introduction to Longitudinal Propagation
Wave motion or vibration is made possible by inertia and elasticity in a material.Because of inertia,matter remains at rest or in uniform motion in the absence of external forces; this permits the transfer of momentum between neighboring particles or elements in a medium.Elasticity designates the tendency of displaced elements to return to their original or equilibrium position after the passage of a disturbance.Air,water,glass,and such metals as steel and iron are relatively elastic.
Wave propagation may be demonstrated by the use of a long helical spring fixed at one end.If a disturbance is imparted at the free end,the motion is carried through the adjacent coils,while at the same time the initially displaced coils tend to return to their former positions.The net effect is to produce two distinct regions that travel down the coil structure:in one,a series of neighboring coils are pushed close together because of the initial action of the disturbance (compression); in the other,the relative spacing of coils is enlarged because of the removal of the disturbing force and subsequent overcompensation by the elastic coils (rarefaction).
The wave nature of sound in air may also be demonstrated by the device presented in figure2.2.
图2.2及其说明
The action of the piston in figure 2.2 alternately pushes the air molecules together or pulls them apart.It is the inherent elasticity of air,combined with inertia,which allows these successive disturbances to travel down the tube as the displaced molecules try to regain their former equilibrium.The net effect on the pressure distribution is maximum pressure amplitude at points of maximum compression and minimum pressure at points of maximum rarefaction.If the disc rotates at a constant speed,then the wave form,as represented by the pressure,will be sinusoidal.Figure 2.3 shows some of the characteristics of this simple wave form,termed a longitudinal plane progressive wave because the elements of the medium are displaced in the direction of propagation and the wave is not stationary in space.Waves that propagate in many duct noise control problems or at large distances in free space from a spherically radiating source closely approximate longitudinal plane progressive waves.
图2.3及其说明
英语翻译把以下文章翻译成英语,公式可略As an illustration of the magnitude of the fluctuations involved,atmospheric pressure is normally 1.012 x 10 5 N/m 2 at sea level; a barely audible signal might fluctuate as little as 10 5 N/m 2
你这个也忒高难度了哦,一般六级的人生词量也太多哦.我是业余翻译freelance,以下是我的翻译:
正如插图所示的波动幅度,大气压在海平面通常是1.012X105牛顿/㎡,在这个数值之下听觉信号(可闻信号)波动仅为105牛顿/㎡,而一个持续不断的恼人的大噪音大概是10牛顿/㎡,也就是说,只有0.01°70的大气压值.(单位牛顿/㎡有些时候也用它的等值帕斯卡Pa来表示.)2.1声音的简单波本质2.1.1纵向传播介绍波动或者说震动,是可以通过物体的惯性和弹力产生的.由于惯性,物体在不受外力作用下处于一种静止或者均匀运动状态.这使得动量在相邻粒子或元素媒介之间进行传递.弹力使得偏离原位的元素在受到干扰后回到原来位置或者平衡位置.空气,水,玻璃以及诸如刚铁等金属都是比较有弹性的(介质).
波的传播已证实应用于长的顶端涡旋弹簧.如果干扰(施加动力)是在自由之承点,那么运动是传递于毗连的线圈,但同时最先移位的线圈将回到它们先前的位置.它的实际效果是产生两个不同的区域来穿过线圈结构.一方面,一系列的相邻线圈由于干扰(压缩)的初作用力推动而靠近,另一方面线圈的相对空间由于外力干扰偏离而扩大,以及有弹力的线圈反弹力的过度补偿而造成.
声波在空气中的本质也可以如图2.2所示设备的演示.
如图2.2所示,活塞运动交替进行推动空气分子在一起和分开它们.空气有内在弹力,由它们的惰性(不活泼性)结合在一起,允许这些接连不断的干扰作用力通过位移分子试图返回预案平衡位置而穿过管子.气压分布的有效效应是最大气压变化幅度在最大压缩点和最小压力在最大稀薄点.如果阀盘以恒定的速度在旋转,那么波的形式,就是如图所示的正弦曲线.图示2.3展示了这些简单波形的特性,被称为纵向推进波,因为传播介质元素偏离波前进的方向因而波是不在固定的空间里的.波在很多导管声音控制问题或者源于球形辐射源的长距离真空传播基本都是纵向行波.
忙着写论文啊老大~
你要下重金才行~
建议自己翻译吧。
图书馆有专业词典,也可能有相关主题的论文(中英对照的那种)。
空气动力学?声学?物理?