This is definitely stupid, think I’m missing something.
If I say something at 60 decibels for example, the person I’m talking to will hear it at that volume (ignoring the sound lost over distance).
But if a crowd of people say something at 60 decibels, it will be louder to the person hearing it.
I just can’t get my head around why, since they’re all talking at the same volume as the single person. What amplifies it?
In: Physics
Go on a computer graphing sim like Desmos, or grab a graphing calculator.
Type in y=sin(x). This will give a visualization of a simple sound wave, let’s imagine that’s what one person saying something looks like.
Now let’s imagine there’s 20 people say the exact same thing at the exact same time. That graph would be y=sin(x)+sin(x)+…+sin(x) AKA y=20sin(x). Look at that graph and you can see that the vertical aspect of the wave (intensity/amplitude) is way more dramatic.
The vertical axis of the graph represents the pressure of the air as the wave hits your eardrum over time (horizontal axis), imagine that when the high part of the wave hits your eardrum, it pushes it in, and when the low pressure part hits, it comes back out. A wave that has a bigger difference between the peak and the trough will move the eardrum more, which will translate to a louder sound in your brain
This is a crazy simplified explanation that ignores a lot of nuance, as well as the destructive interference that can often take place in crowds, but that is the general principle.
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