The child at this age turns his head to locate the source of sound.

这个年龄的孩子会转过头去找声音的来源。

The Doppler effect is the frequency shift heard as a source of sound approaches or recedes.

多普勒效应是当声源靠近或后退时听到的频率偏移。

What you're experiencing is called tinnitus, the perception of a noise like ringing, buzzing, hissing or clicking that occurs without any external source of sound.

您遇到的情况称为耳鸣，即在没有任何外部声源的情况下发生的铃声、嗡嗡声、嘶嘶声或咔哒声等噪音。