英语翻译声波的多普勒效应在日常生活中,我们都会有这种经验：当一列鸣着汽笛的火车经过某观察者时,他会发现火车汽笛的声调由高

英语翻译
声波的多普勒效应
在日常生活中,我们都会有这种经验：当一列鸣着汽笛的火车经过某观察者时,他会发现火车汽笛的声调由高变低.为什么会发生这种现象呢?这是因为声调的高低是由声波振动频率的不同决定的,如果频率高,声调听起来就高；反之声调听起来就低.这种现象称为多普勒效应,它是用发现者克里斯蒂安•多普勒的名字命名的,多普勒是奥地利物理学家和数学家.他于1842年首先发现了这种效应.为了理解这一现象,就需要考察火车以恒定速度驶近时,汽笛发出的声波在传播时的规律.其结果是声波的波长缩短,好像波被压缩了.因此,在一定时间间隔内传播的波数就增加了,这就是观察者为什么会感受到声调变高的原因；相反,当火车驶向远方时,声波的波长变大,好像波被拉伸了.因此,声音听起来就显得低沉.
光波的多普勒效应
具有波动性的光也会出现这种效应,它又被称为多普勒-斐索效应.因为法国物理学家斐索（1819~1896年）于1848年独立地对来自恒星的波长偏移做了解释,指出了利用这种效应测量恒星相对速度的办法.光波与声波的不同之处在于,光波频率的变化使人感觉到是颜色的变化.如果恒星远离我们而去,则光的谱线就向红光方向移动,称为红移；如果恒星朝向我们运动,光的谱线就向紫光方向移动,称为蓝移.
物体辐射的波长因为波源和观测者的相对运动而产生变化.在运动的波源前面,波被压缩,波长变得较短,频率变得较高 （蓝移blue shift）；当运动在波源后面时,会产生相反的效应.波长变得较长,频率变得较低 （红移red shift）.波源的速度越高,所产生的效应越大.根据波红（蓝）移的程度,可以计算出波源循着观测方向运动的速度.

The sound wave doppler effect
In daily life,we can have this kind of experience:when a listed sound of the train whistle after one observer,he will find the train whistle of tone changes from high to low.Why will happen this phenomenon?This is because the discretion of the tone is by sound waves of vibration frequency of different decision,if high frequency,tone sounds is high; And tone sounds is low.This phenomenon is called doppler effect,it is to use the discoverer kristian doppler name,doppler is Austrian physicists and mathematicians.In 1842 he first discovered this effect.In order to understand the phenomenon,need to examine the train is approaching constant speed,the sirens of sound in a spread of the law when.The result is sound waves wavelength shorten,like wave is compressed.Therefore,in a certain time intervals of transmission wave number increases,and this is why will feel tone change observer reasons of high; Instead,when the train to far away,the wavelength of sound waves change,like wave by drawing.Therefore,the voice sounds is low.
The light wave doppler effect
The light of the volatility has also will appear this kind of effect,it has been called the doppler-which cable effect.Because the French physicist ophir cable (1819 1896) in 1848 to independently from star explains the wavelengths,and points out that the use of this effect to the relative speed measuring star.Light waves of sound and the difference is,light waves frequency changes make the person feel is color change.If stars far away,the light spectrum line to red light direction,called red shift; If stars towards us movement,the light spectrum line is moving to the direction,called blue shift.
The wavelength of the radiation object because waves and the relative motion of the observer and produce change.In the movement of the front waves,wave be compressed,wavelength becomes short,are higher frequency (blue shift); When movement in waves behind,to have the opposite effect.Wavelength becomes longer,frequency become low (red shift).The higher the speed of the waves,the greater the effect of.According to wave red (blue) moving degree,can calculate the waves followed the observation direction of movement speed.