Doppler effect
01
多普勒效应, 多普勒现象
the change in frequency or wavelength of a wave in relation to an observer who is moving relative to the source of the wave, producing a shift in pitch or color
例子
The Doppler effect explains why the pitch of an ambulance siren changes as it approaches and then passes by.
多普勒效应解释了为什么救护车警报器的音调在接近然后经过时会发生变化。
When a car with a honking horn drives by, the change in pitch you hear is due to the Doppler effect.
当一辆鸣笛的汽车驶过时，你听到的音高变化是由于多普勒效应。
