Question: why does sound travel faster than water ?

Sophie Holles answered on 21 Mar 2013:

Sound travels faster underwater than in air because sound travels by vibrations of particles knocking into each other. If the material is more dense, the particles are closer together, so it can knock onto the next particle more quickly. So sound travels faster in water than air, and faster in solids like rock than in water. Sound can’t travel at all in space because there are no particles to transmit the vibration! That’s why in space no one can hear you scream.