How does the sound travel?

Sound travels as a mechanical wave through vibrations in a medium like air, water, or solids.

When an object vibrates, it creates compressions and rarefactions in the surrounding particles. These disturbances move forward as sound waves. Sound cannot travel in a vacuum because there are no particles to carry the vibrations. The speed of sound depends on the medium: it is fastest in solids, slower in liquids, and slowest in gases.

• Sound needs a medium (air, water, solids)
• It travels as longitudinal waves
• Speed of sound in air: about 343 m/s
• No sound in vacuum