Eli5 Why can light not carry sound?

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From my very limited understanding sound is basically the vibrations in particles/atoms/ whatever, and light is some sort of weird mix between energy and very small particles, so why can light not carry sound? ( sorry if grammar/wording is bad high)

Edit: woke up to all of this, thank each and everyone of you so much!

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14 Answers

Anonymous 0 Comments

The basic explanation is that sound is vibration in a gaseous medium that can interact with our eardrums. Light doesn’t interact with your eardrums, thus you can’t perceive it as sound. Instead, its frequencies you see as different colors (in the visible spectrum) it can “vibrate” at frequencies much higher and lower than what you can see.

But, you can use light as a carrier of information, using that to communicate sound to a machine that can interpret that back.

Anonymous 0 Comments

sound is what vibrates your ear drum, ultimately, that’s what has to happen. light doesn’t have enough momentum to vibrate anything like that until it’s so intense you start incinerating things instead.

Anonymous 0 Comments

Humans generally can hear vibrations between 20 and 20,000 hertz. Light has frequencies in the range of 420 to 750 trillion hertz, way beyond us.

Anonymous 0 Comments

The other answers here kind of cover it. There’s one more thing missing, though, as light is (mostly) not self-interacting.

Any change in that light will travel outwards at the speed of light. The photons don’t bounce off of one another to carry pressure waves forward. Only in the most extreme examples does light interact with itself, and the math to figure out if it could carry anything like a sound wave is beyond me.

Anonymous 0 Comments

when light comes to a point it is physically capable of vibrate your eardrums in a frequency ranges you can perceive..
well..
let’s just say you have more pressing issues than listening

Anonymous 0 Comments

Light is travelling so much faster than sound can and sound can’t travel in a vacuum, what you can do is have the two associated with each other in lightning. https://youtu.be/NQiqXdEHL_Q

Anonymous 0 Comments

Sound waves are waves of pressure in a medium (liquid, gas, solid, etc.). We perceive pressure waves in the air that hit our ear drum as sound. That’s how we hear, waves of pressure in the air hitting our ear drums.

Light waves are not waves of pressure. Light waves do not require a medium to travel; they can travel though nothing just fine (e.g., the vacuum of space). We have receptors that can detect light: our eyes.

So just as our eyes can’t see sound, our ears can’t hear light. While light waves and sound waves do have some macro scale similarities, in reality they are two very different things.

Light can also be considered both a wave and a particle (further explanation is a bit beyond the scope of this question) and behaves according to the laws of quantum physic. Whereas sound is just a wave of pressure traveling through something (like air).

Anonymous 0 Comments

Sound is mechanicsl wave. Atoms physically change their positions.

Light is an electromagnetic wave. Electromagnetic field changes its properties, but atoms themselves are not moving.

Anonymous 0 Comments

Light can carry sounds, but not the way you think. We can use light to carry information about sound, but need a device to interpret it. That’s what radio is, for example – converting sound to light waves, broadcasting them, and using machines to take that information and reproduce the original sound.

Anonymous 0 Comments

Light can carry the same information sound does. For example, you can bounce a laser off a window, use a light sensor to pick up the reflection, and play it on speakers to hear what’s going on in that room.

You just can’t hear light, at least not directly, because light won’t perceptibly move your eardrums. At least not at any safe or reasonable power level. Doubly so because it’s difficult for light to get to your eardrums in the first place.