Sound travels faster in water than in air primarily due to differences in the density and compressibility of these mediums.
In general, sound waves propagate through the vibration and compression of particles in a medium. The speed of sound is determined by the medium's properties, such as density and compressibility. Let's examine the factors contributing to the higher speed of sound in water compared to air:
Density: Water is denser than air. The closer the particles are to each other in a medium, the faster sound can travel because the neighboring particles can transmit the vibrations more efficiently. The higher density of water allows sound waves to propagate more quickly compared to the lower density of air.
Compressibility: Compressibility refers to the ease with which a medium can be compressed when subjected to pressure. Water is significantly less compressible than air. In other words, it takes much more pressure to cause a given volume of water to compress compared to the same volume of air. As a result, sound waves in water experience less resistance and are able to travel faster.
To provide some numbers, the approximate speed of sound in dry air at 20 degrees Celsius is about 343 meters per second (m/s). In contrast, sound travels at approximately 1,482 m/s in fresh water at the same temperature. This means that sound travels over four times faster in water than in air.
It's worth noting that the speed of sound can vary with different factors such as temperature, salinity, and pressure. For example, as temperature increases, the speed of sound generally increases in both air and water.
In summary, the higher density and lower compressibility of water compared to air allow sound waves to propagate faster in water. These factors enable the particles in water to transmit vibrations more efficiently, resulting in a higher speed of sound.