Do the mirrors move through sound?
No, they don’t! Just stand next to the mirrors and ask someone to beat the drum. You will hear the beat before the mirrors start to swing! Sound travels so fast that it reaches the mirrors after only one hundredth of a second. The mirrors move because of the wind made by the drum. It takes about a second for it to reach the mirrors.
A wind of 34 metres per second is already called a hurricane, while sound reaches 340 metres per second in the air.
Speed of sound in water
Do you think sound travels fast in the air? In water, it travels four times faster: about 1,500 metres per second. Many animals that live underwater communicate using sound.
Speed of sound for aircrafts
If an aircraft flies faster than the speed of sound, a very loud bang is produced. They also say that the aircraft “breaks the sound barrier”.
You also hear such a sonic boom when you strike with a whip.