Why is sound faster in water than in air?

Sound is faster in water than in air because water is denser and less compressible, allowing sound waves to travel more quickly.

Sound travels through different mediums by causing the particles in these mediums to vibrate. The speed at which these vibrations, or sound waves, travel depends on the density and compressibility of the medium. In air, the particles are spread out and can be easily compressed, which slows down the speed of sound. On the other hand, water is denser, meaning its particles are closer together, and it is less compressible. This allows sound waves to travel faster through water than through air.

The speed of sound in air is approximately 343 metres per second, while in water it is around 1,500 metres per second. This significant difference is due to the properties of the two mediums. The molecules in a gas like air are far apart from each other, which means they need more time to transmit the vibration from one molecule to the next. In contrast, the molecules in a liquid like water are much closer together, so the vibration can be passed on more quickly.

Moreover, the compressibility of a medium also affects the speed of sound. Compressibility refers to the degree to which a substance can be compressed. Air is highly compressible, which means it can absorb some of the energy of the sound wave, slowing it down. Water, however, is much less compressible. This means it absorbs less of the sound wave's energy, allowing the wave to travel faster.

In conclusion, the density and compressibility of a medium significantly influence the speed at which sound travels. Therefore, due to water's higher density and lower compressibility compared to air, sound travels faster in water.