how do waves look in 3 dimensions? every representation i've been exposed to seems to reduce it to 2 dimensions.
isn't it more like a series of spheres that expand from a focal point, where they each compress and expand the medium they move through if it's mechanical? i don't know how it would behave in the EM sense.
i guess it's better to ask if waves are just fields that propagate themselves. it just doesn't make sense to me to see a wave moving in one direction.
like this makes sense. why isn't this the way it's shown?
It depends on the type of wave.
Longitudinal waves, like sound waves, look like stuff moving back and forth along the wave axis
Transverse/Dipole waves, like electromagnetic waves, are in fact moving back and forth in a plane parallel to the wave axis. This is why light has a polarization.
Quadrupole waves, like gravity waves, are more complicated - in cross-section (xy plane, wave traveling along z axis), imagine a circle squishing in the x and stretching in the y to form a vertical ellipse, then squishing in the y and stretching in the x to form a horizontal ellipse.
Waves are just some quantity that oscillate in value over time and/or space.
E.g. EM waves only really act in one spatial dimension, the oscillation is just in the strength of the E and M fields.
That's only if the waves expand radially, if it's a plane wave it looks pretty different
so it's not an oscillation of matter but energy?
but i thought all waves expand radially because fields are radial.
>fields are radial
Do colorless green fields sleep radially?
I want you to take out a laser pointer and point at the wall. Does the light seem to be expanding from the source in uniform, omnidirectional spheres? If so, the wall behind you and the ceiling should also be illuminated with similar strength, depending on their distance from the source.
when the source is too far, you can always approximnate to a plane wave, thats why you don't usually see this kind of representation .
Also, a radiation pattern graph is much more useful and easy to understand than making a complicated 3D represantiation of the waveform
Do all water waves expand radially? If so, how do wave pool machines work?
>when the source is too far, you can always approximnate to a plane wave, thats why you don't usually see this kind of representation
Thank you. Additionally, dipole radiation (like EM) doesn't really follow a sphere pattern - it's only created by a varying dipole moment, and so along the dipole axis there's no radiation. You get more of a toroidal pattern.
Waves are just pressure differences in a sense
it's just reflecting radial waves at multiple points which combine to form a traversing wave?
>so it's not an oscillation of matter but energy?
It's an oscillation of anything
even of time? woah................
An oscillation of anything over time and space to be more precise
how can it be over space? you mean like a car wheel covering distance?
Kind of, as in the wave needs to move through space in some direction
can waves move in closed paths?
have some gifs of transverse EM waves
...
>can waves move in closed paths?
see
STANDING WAVE