Eli5 This might be stupid, but is sound louder on planets with thicker atmospheres than earth’s because there are more air molecules that carry the sound vibrations? If so, would it be vice versa for planets with thinner atmospheres than earth’s?

506 views

Eli5 This might be stupid, but is sound louder on planets with thicker atmospheres than earth’s because there are more air molecules that carry the sound vibrations? If so, would it be vice versa for planets with thinner atmospheres than earth’s?

In: Earth Science

2 Answers

Anonymous 0 Comments

Not exactly. The sounds will be higher pitched as the density decreases. You can also more efficiently impart energy into the air. For the same amount of energy actually imparted into the air the level of sound will be the same.

Anonymous 0 Comments

The amount of energy in the sound waves and therefore how loud the sound is remains the same no matter what the sound travels through. Different materials and different pressures does cause different impedances but this only matters when transfering the sound between materials with different impedance and not how loud the sounds are.

What you do get with different pressures however is how loud the maximum volume can be. Sound is waves of varying pressure so it is possible that a sound wave creates vacuum or at least very close to a vacuum. And since you can not create pressures lower then vacuum the volume of the sound is sort of capped. This is the same thing that happens when you max out a microphone or speaker and you start getting that ugly cracking sound. You can hear the exact same sound during rocket launches when the sound generated by the rockets gets above what the pressures on Earth is able to carry. And with a lower pressure this would happen at lower volumes. For example you are able to carry human voices and similar sounds in the Martian atmosphere however and louder sounds like a hammer hitting a rock will sound muffled and broken because there is not enough pressure in the atmosphere to carry the sound.