If sound goes through solids more easily than air, how do foam and silicone earplugs sound instead of amplifying it when it hits your ears?

Question

If sound goes through solids more easily than air, how do foam and silicone earplugs sound instead of amplifying it when it hits your ears?

In: 9

Answer 1

**Edit**. See the response below mine.

“More easily” isn’t really the best way of thinking about it.

The more dense the material, the faster the speed of sound (or a pressure wave) travels though it, but the more energy it takes to create that wave.

You don’t get anything for free, the sound wave speeds up, but its power is then reduced. So when the sound wave comes out the other end of the denser material, it’s slower again, but also at much lower power.

Transitioning between materials takes a lot of the energy out of the equation, which results in lower volume.