Surfing with electromagnetic waves

AI Thread Summary
Electromagnetic waves can accelerate charged objects through momentum transfer, primarily affecting their direction rather than linear speed. The interaction of EM waves with particles is described by Maxwell's equations, which detail how waves reflect off surfaces due to electron oscillations. Unlike gravity, which does not reflect, electromagnetic waves can be absorbed and re-emitted by materials, leading to reflection. Classical electrodynamics alone is insufficient for explaining optical phenomena at the atomic level, necessitating quantum mechanics for a complete understanding. This discussion highlights the complexities of wave interactions and the limitations of classical physics in explaining modern optics.
HomogenousCow
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Let's say I have some source that generates a spherical wave that propagates outwards at the speed of light, and I have a vehicle that is charged.
The wave will accelerate my vehicle periodically and eventually bring it to great speeds.
Does this work?
 
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Spherical wave of what?
Electromagnetic waves are transversal - the main acceleration of your charged object would be sidewards, and changing its direction with the frequency of the electromagnetic wave.
The charged object would absorb or reflect some fraction of the wave, which gives an effective acceleration in the direction of the beam - but you do not need to charge the whole object, everything non-transparent will work. Solar sails use this concept.
 
hmm right.
Actually I'm a bit confused, could someone correct me if I'm wrong.
As i understand it, EM waves are just solutions to maxwells equations and they themselves interact with particles, transferring momentum in the form of a force?
And by the way, why do EM waves reflect off of surfaces? That has always bothered me.Gravity certainly does not reflect off of things, why electromagnetic waves?
 
As i understand it, EM waves are just solutions to maxwells equations

and they themselves interact with particles, transferring momentum in the form of a force?
They can do that.

And by the way, why do EM waves reflect off of surfaces?
As quantum mechanical description: Electrons (and sometimes other particles) can absorb the energy and re-emit it.
As classical description for metals: EM waves can lead to oscillations of electrons in the surface, those emit electromagnetic waves.

You cannot compare electromagnetic waves to gravity in that way. I think gravitational waves can be scattered in material - but gravity is so weak, we cannot even detect the waves themself with current experiments (might change in 2-3 years), so this is just a theoretic thing.
Gravity (as force between matter) does not reflect, and neither do electrostatic forces (as forces between charges)
 
I was hoping for a more elegant classical explanation..but I guess that makes sense.
So basically classical Electrodynamics is not enough to explain optics?
 
It cannot explain atoms or solid objects without effective theories (like a refraction index and so on). As soon as you want to understand that on a microscopic level, you need quantum mechanics.
 
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I was using the Smith chart to determine the input impedance of a transmission line that has a reflection from the load. One can do this if one knows the characteristic impedance Zo, the degree of mismatch of the load ZL and the length of the transmission line in wavelengths. However, my question is: Consider the input impedance of a wave which appears back at the source after reflection from the load and has traveled for some fraction of a wavelength. The impedance of this wave as it...

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