I really can’t grasp the concept of waves. I can imagine it a bit for sound waves: a speaker has a surface that pushes air, and the moving air eventually pushes the membrane in our ears.
But I’m confused about wifi etc. What exactly is the thing that physically travels? Is it air or something else? Does it physically move in a wavy pattern?
Edit: thanks for all the answers! But damn I’m overwhelmed. It’s gonna take me days to read and fully understand the answers. But thanks!
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Electromagnetic waves have very weird motion because if you take a “drop” of electrical field and then “throw” it, it’ll generate magnetic fields in a corkscrew motion around it as it picks up speed.
Likewise, a “drop” of magnetic field, when “thrown” will generate electric fields in a corkscrew motion around the magnetic field.
Electro magnetic waves travel because whenever an electric field speeds up, it’ll create a speeding up magnetic field which creates a speeding up electric field which creates a speeding up magnetic field which creates…
Imagine a sheet of electric field moving to the right this will generate a sheet of magnetic field in front of it which moves up. That will generate a sheet of electric field in front of it moving left. That will generate a sheet of magnetic field in front of it moving down. So as the wave moves forward, you get electric fields moving left and right and magnetic fields moving up and down. Note that the movement of the electric and magnetic fields are never in the same direction as each other, or the wave’s motion.
“Wait, where did the corkscrew motion go when we switched to moving sheets?” Imagine that an electric field sheet is just a bunch of electric field “drops” thrown together, all right next to each other. Now, the corkscrewing magnetic fields all overlap and the corkscrews cancel out into a sheet.
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