Sound is vibrating air. But how does the air start vibrating? Explore the intriguing science of sound waves and how they travel. Learn how speakers use oscillation to create sound, and discover why sound waves can transport energy without moving the medium itself. Uncover the mystery behind the difference in our voices in person and on recordings. Created by David SantoPietro.
Want to join the conversation?
- i need this explained in spanish(12 votes)
- Las vibraciones hacen que las ondas de presión en el aire ( o cualquier otro medio de la materia) que propagar a la velocidad del sonido. Nuestros oídos detectan las ondas de presión y nuestro cerebro convierte las vibraciones detectadas en sonido.(69 votes)
- How can sound waves travel through our flesh?I mean why don't they get obstructed?Also,what is the criteria or the mechanism between sound proof rooms?How are the sound waves getting obstructed in this case?(10 votes)
- Sound is simply vibrations. Sound can travel through any medium where it can make neighboring particles vibrate to the same frequency, which is why sound can travel through any medium, including water and even our flesh. Sound proof rooms will have something on the walls, often some a soft and sponge, that will absorb the vibrations in the air and prevent it from passing through the room. Perfectly sound proof places might even be enclosed by a vacuum. (Note: there is no sound in space because there is no air for vibrations that cause sound)(31 votes)
- why does everyone sound different from each other ?(4 votes)
- That's more a matter of biology and physiology than physics. It's to do with your larynx and speech patterns.(13 votes)
- At0:43, he said that the air doesn't actually ever move away from the speaker, why does this happen?(4 votes)
- When the diaphragm moves into the air, it pushes the air molecules into each other creating a region of higher pressure (more molecules per unit volume). When the diaphragm moves away it creates a region of low pressure. The oscillating diaphragm thus creates oscillations of pressure in the air which we perceive as sound. The diaphragm vibrates continuously. So the air molecules doesn't move away from speaker. Hope this is clear and helps you.
CREDITS : Doublestack @Dirac76.(11 votes)
- How come if something is producing sound, it gets quieter when I'm further from it, and louder when I'm close to it?(4 votes)
- For two reasons:
1) The sound energy gets spread out over a bigger and bigger area as it moves away from the source
2) The sound energy dissipates as it moves through the air, because of friction-like effects among the air molecules.(7 votes)
- Why does the air oscillate? Why doesn't it just move forward?(2 votes)
- I thought it was more that the molecule is hitting molecules next to it, and so it is blocked and just transfers energy, then the molecules it hits do the same to the molecules next to them and so on.(3 votes)
- Could you please help me with this question.
May we say that kinetic energy is the signature of sound?
- at1:00, won't the particles of air collide(meaning touch each other) and transfer energy(sound energy) and also loose some energy during the collision?it means the particles wont come back to their initial position and hence travel some displacement?this means sound makes the particles cover some displacement and hence is not a wave. how is this possible?(3 votes)
- every action has an equal and opposite reaction
in this cause when the initial particlehit the next one it too acquires the same amount of energy to move back so then it do make wave(1 vote)
- do only vibrating object produce sound . is there any other way by which sound waves are produced ?(2 votes)
- Anything that causes molecules to vibrate produces sound, could be a chemical reaction (explosion) or wind blowing in a tube.(2 votes)
- We have learnt that sound is a fast vibration. Isn't the amount of vibration same on all creatures? If so, Why does sound differ in creatures?(2 votes)
- What do you mean by 'amount of vibration?' Are you talking about the frequency? Also, are you taking about the sound creatures make?
If so, then no, different creatures make different sounds because the way they make sound differs in different creatures, changing the frequency and timbre, or the 'texture' of the sound.(2 votes)
- Check out this speaker. If we plug it in, it makes sound. (speaker hums) The way this speaker creates sound is by moving the front of the speaker, which is called the diaphragm, back and forth rapidly. Scientists often use the word oscillation to refer to the back and forth motion of an object. This speaker is oscillating too fast for the human eye to see, but if I put a piece of paper on the speaker, we see that because the diaphragm is oscillating, it's bumping into this piece of paper and causing it to dance. The oscillation of the diaphragm will also cause the air in front of the diaphragm to move back and forth, but here's the interesting thing. The air in front of the diaphragm doesn't actually travel away from the speaker. The air molecules in front of the speaker just oscillate back and forth. So, how can you hear the sound from a speaker if the air next to the speaker doesn't actually make it to your ear? Well, the reason is that the oscillating air in front of the speaker causes the air in front of it to also oscillate. This causes the air in front of that air to start oscillating, which causes the air in front of it to start to oscillate, until finally, the air that's actually next to your ear and your eardrum starts to oscillate back and forth. This oscillating air that's next to your ear is moving, so it has kinetic energy. So, it can transfer energy into your eardrum, which you can perceive as sound. So, this speaker was able to transport energy through the air, without actually having to transport the air itself. This is an important enough fact for me to state again. Energy is traveling across the room here, but air itself is not traveling across the room. Only the disturbance within the air is traveling across the room. If air were being transported across the room, it'd be better characterized not as sound but as wind. So, this is why we call sound a sound wave, because it shares the defining feature of waves, which is being able to transport energy through a medium without having to transport the medium itself. Medium is a fancy word for the material or substance through which a wave is traveling. Air is typically the medium for situations involving sound waves, but sound waves can travel through all kinds of different materials, like water, metal, or even human flesh and bone, and the fact that sound can travel through human flesh and bone explains something you might have always wondered about, which is, why do our voices sound (changes voice) so different on audio and video recordings? The reason for this is that when we're speaking to someone we actually hear two contributions from our voice. We hear the sound wave traveling out of our mouth, through the air, and into our ear, but we also hear the vibration of the sound wave traveling through our flesh and bone, through our skull, and into our eardrum. But on an audio or video recording, the only part that's recorded is the sound that travels through the air. So, when you hear your voice played back on an audio recording, you only hear what other people hear when they listen to you. So, the bad news is that, yes, what you hear on audio recordings is actually what you sound like to other people, but the good news is that most of your friends probably don't think it sounds weird, since that's the only voice they've ever heard you use, unless you do (changes voice) actually have a weird voice, in which case, I'll risk sounding pretentious by reminding you that you shouldn't waste a lot of time worrying about what other people think of you anyways. (techno music)