It is caused by the Doppler effect (something similar happens when a police car or fire engine with its siren blaring drives past you, and the pitch of the sound suddenly drops).

这是由多普勒效应(类似一辆警车或消防车鸣着警笛从你身边经过，之后音高突然下降)引起的。

youdao

The Doppler effect is used to discover extrasolar planets.

都卜勒效应通常用于探索太阳系外行星。

youdao

This paper introduces the Doppler effect on OFDM system in mobile environment.

分析了在高速移动环境下存在的多普勒效应，指出了它对OFDM系统的影响。

youdao

The Doppler effect explains changes in the length of light waves or sound waves as they move toward you or away from you.

VOA: special.2009.04.29

Suddenly they do the Doppler effect where they turn their backs to you, in a way, and they're marching away from you and you hear very little sound.

突然,他们也产生了多普勒效应,当他们转身背对你时,当他们背离你前进时,你会听到一种很微弱的声音

耶鲁公开课 - 聆听音乐课程节选

It also is known as the "Doppler effect."

VOA: special.2009.04.29

This exploits the Doppler effect familiar when a siren changes pitch as the fire engine on which it is mounted speeds past you.

ECONOMIST: Is there anybody out there?

This is a reddening of a galaxy's spectrum caused by the Doppler effect (the effect that causes a police-car siren to drop in pitch as the car drives away).

ECONOMIST: Astronomy

Just as you could use the Doppler Effect to pinpoint the location of a satellite flying overhead, you could also employ satellite signals to find your own location on the ground.

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