The speed of sound (propagation of sound) indicates how quickly acoustic waves travel through a given medium. Under standard conditions, at a temperature of 15 °C, the speed of sound is 340.3 m/s, or about 1225 km/h. Any change in atmospheric conditions or air parameters simultaneously affects this speed. The lower the temperature, the lower the speed of sound, while it increases at higher temperatures. For example, at 40 °C, it is 355.3 m/s.
The propagation of sound in selected substances depends on how quickly energy from the vibrations of molecules is transmitted in that substance. In the case of low sound intensity, the vibration of molecules will be smaller, but this does not affect the speed of sound. It is independent of that.
The first measurement of the speed of sound was made around 1636 and is attributed to Marin Mersenne.
Below is an example of the speed of sound in selected substances:
carbon dioxide: 259 m/s;
air: 340 m/s;
helium: 965 m/s;
hydrogen: 1284 m/s;
water, mercury: 1500 m/s;
ice: 3300 m/s;
concrete: 3800 m/s;
steel: 5100-6000 m/s;
glass: 6000 m/s;
diamond: 18,000 m/s.
