Two factors affect the speed of a sound wave as it travels through a medium

The density and the temperature

Explanation:

Sound needs a medium to travel. The medium particles vibrate and transfer energy. Sound travels by compression and rarefaction of the medium particles. Thus, the speed of the sound varies with the density of the medium. If the medium is denser, the particles would be closer and energy would transmitted faster because there would be more rapid collisions which means that speed of the sound will be greater in a denser medium. Thus, speed of sound is fastest in solids than in liquids and is least in gases.

Speed of sound also depends on temperature. Greater the temperature, the particles would vibrate faster which would lead to again more inter particle collisions. Thus, the speed of sound would increase with increase in temperature.

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