Why does sound travel quicker through aluminum than air?

Answer 1

Sound can travel through anything, except vacuum. Sound is the vibration of molecules, passing the vibration on to other molecules. As long as there's molecules, the sound can travel through it. However, the sound will slowly fade because every time a molecule gives the energy to another, a little energy is lost. And therefore, the more molecules you have, the more the energy will fade before passing through, and the weaker the sound will become. Eventually, the sound will be reduced to nothing. That happens in everything, but in some media it happens faster than in others.

Answer 2

Sound will travel faster through any material that is more dense (i.e. the atoms are closer together) sound travels by vibration of particles, if an atom doesn't have to move as far to hit the next atom then the sound will travel much faster. This can actually be modeled really well by using pool balls.

Answer 3

Sound is basically vibrations perceived to be sound by the cochlea in the ear. These vibrations can move through solid objects and liquids. Sound does not travel in the air; it vibrates the air molecules one after another.