Transferring between mediums is a large impediment for sound, it loses a lot of energy that way. So for sound to go air-solid-air, it’s 2 transfers compared to directly into your ear.
When “sound travels through something” it’s one particle bumping into the next particle beside it, which then bumps into the one beside it, and so on. It’s a chain of physical collisions bumping along, from the source of the sound to your ear. Each collision absorbs a little of the energy which is lost as heat.
The particles in a gas are fewer and farther apart than in a solid. Not surprising!
Now think of a sound going through them. If the particles are all packed in super close together, the chain of collisions can happen really fast because each particle only has to move a tiny bit to hit its neighbour. But that also means there’s a ton more collisions along the way from the source to your ear. More stuff is being moved so the sound energy gets absorbed and lost along the way more quickly.
In a gas the chain of collisions moves slower because each particle doesn’t hit a neighbour for a bit, but that also means less energy loss along the way
“Faster” is only about the time it takes to arrive, not the proportion of the energy that makes it to the destination.
If it’s only traveling through a solid, it’s actually easier to hear. Get a wire coathanger and about 3 feet of string. hang the coathanger in the middle, and hold the ends of the string to your ears, now knock it against something.
What makes it harder to hear is crossing boundaries between mediums of different density. If you have metal and air carrying the same amount of sound energy, the air moves a lot more, and the metal pushes a lot harder over a shorter distance If you try to transfer energy from one to the other, most of it just bounces off. One way to get around this is to use the piece of metal to vibrate a large membrane, so it can push on more air at once. This is what the cone is for in a speaker.
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Transferring between mediums is a large impediment for sound, it loses a lot of energy that way. So for sound to go air-solid-air, it’s 2 transfers compared to directly into your ear.
For the same reason!
When “sound travels through something” it’s one particle bumping into the next particle beside it, which then bumps into the one beside it, and so on. It’s a chain of physical collisions bumping along, from the source of the sound to your ear. Each collision absorbs a little of the energy which is lost as heat.
The particles in a gas are fewer and farther apart than in a solid. Not surprising!
Now think of a sound going through them. If the particles are all packed in super close together, the chain of collisions can happen really fast because each particle only has to move a tiny bit to hit its neighbour. But that also means there’s a ton more collisions along the way from the source to your ear. More stuff is being moved so the sound energy gets absorbed and lost along the way more quickly.
In a gas the chain of collisions moves slower because each particle doesn’t hit a neighbour for a bit, but that also means less energy loss along the way
“Faster” is only about the time it takes to arrive, not the proportion of the energy that makes it to the destination.
If it’s only traveling through a solid, it’s actually easier to hear. Get a wire coathanger and about 3 feet of string. hang the coathanger in the middle, and hold the ends of the string to your ears, now knock it against something.
What makes it harder to hear is crossing boundaries between mediums of different density. If you have metal and air carrying the same amount of sound energy, the air moves a lot more, and the metal pushes a lot harder over a shorter distance If you try to transfer energy from one to the other, most of it just bounces off. One way to get around this is to use the piece of metal to vibrate a large membrane, so it can push on more air at once. This is what the cone is for in a speaker.