EM Waves & Forces: Does a Particle Feel Force?

AI Thread Summary
A particle in the path of an electromagnetic (EM) wave can experience a force due to the electric and magnetic fields present in the wave. EM waves can indeed cause charged particles to move, as demonstrated by radio antennas where radio waves induce electron movement. When photons collide with particles, such as a silicon atom, they can impart momentum despite being massless, due to their energy and momentum properties. The discussion highlights that conservation of momentum allows for the transfer of force from photons to particles. Overall, the interaction between EM waves and charged particles is significant and complex.
VishalChauhan
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Would a particle kept in the path of an electromagnetic wave experience a force?
Both magnetic and electric field are present, so the equation of motion may be complex, but i have never seen my textbook refer to the the possibility of an em wave causing a charged particle to move.
 
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EM waves cause particles to move all the time. That's how a radio antenna works - the radio wave causes the electrons in the antenna to move, which produces a current, which is detected by the radio receiver.
 
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So if a charged particle is kept in a ray of light, would it begin to accelerate?
 
I'm not sure what you mean by "kept in a ray of light", but yes, the EM field of light can accelerate charges.
 
Well of course a light wave can accelerate a charged particle, an EM wave has the M part in it, which would affect a charged particle.

What I've always wondered is, if you had, say, an atom of silicon floating in space and a stream of photons came flying at it, a few photons would hit the silicon atom. Would these collisions cause the silicon atom to move?

I know a photon is massless, so conservation of momentum says no, but it also has a lot of energy attached to it (doesn't it?) so from E=mc^2, shouldn't it be able to impart some force?
 
The photon has momentum even though it's massless. So there is no contradiction. Conservation of momentum does not say "no".:smile:

But I think you should start a new topic, as you bring a different question.
 
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