Classical electromagnetic theory

  • #1
Vaibhav Dixit 1008

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According to classical electromagnetic theory,for acceleration a particle must not only change its direction but it should also increase its speed. But Maxwell said that a particle accelerates then it radiates energy.(this is with reference to Rutherford model). But actually the particle is not accelerating because it is changing its direction not speed. So is classical theory wrong or Maxwell didn't get classical theory or Rutherford a genious..??
 

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  • #2
Nugatory
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But actually the particle is not accelerating because it is changing its direction not speed.
A change in direction is an acceleration too.
 
  • #3
Vaibhav Dixit 1008
But according to classical electrodynamics
If a particle is to accelerate then it should not only change its direction but speed must also change.
 
  • #5
Vaibhav Dixit 1008
I know that we can have acceleration and constant speed at same time.
But according to classical electrodynamics a particle must also change its speed in order to accelerate during uniform circular motion.
 
  • #6
cnh1995
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But according to classical electrodynamics a particle must also change its speed in order to accelerate during uniform circular motion.
Then how is that circular motion uniform?
 
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  • #7
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But according to classical electrodynamics
If a particle is to accelerate then it should not only change its direction but speed must also change.
Can you cite your source for this? I think you may just be misunderstanding some other point that is being made
 
  • #8
tech99
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According to classical electromagnetic theory,for acceleration a particle must not only change its direction but it should also increase its speed. But Maxwell said that a particle accelerates then it radiates energy.(this is with reference to Rutherford model). But actually the particle is not accelerating because it is changing its direction not speed. So is classical theory wrong or Maxwell didn't get classical theory or Rutherford a genious..??
Did Maxwell actually say that? I thought it was JJ Thompson and JJ Larmor a few years later.
 
  • #9
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Not helpful.
 
  • #10
Vaibhav Dixit 1008
Let me make it more theoretical
When we talk about limitations of Rutherford model, Maxwell quoted that an accelerating charged particle radiates energy and its energy continuously decreases and it comes to rest. But this term acceleration doesn't fit here.
According to law of classical electrodynamics if a charged particle is to accelerate then it must increase its speed. There is a clause here that the speed of particle should neither be constant nor be decreasing. It should increase. So I think Maxwell said wrong thing.
 
  • #11
Vaibhav Dixit 1008
Now I come to another point. Bohr was really clever. He said that particle doesn't radiate energy. How can that be possible??
See what Bohr actually did. He did a clever usse of law of electrodynamics. According to Bohr a particle can move from low energy level to high energy level. In doing so it doesn't radiate energy because magnitude of velocity decreases which is in coordination with law. Now after 10 raised to power -8 seconds it returns back. Now speed of particle increases. It radiates energy. That's what I want to say.
Now tell Maxwell was not a good student.
 
  • #12
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According to law of classical electrodynamics if a charged particle is to accelerate then it must increase its speed.
We keep telling you this is wrong and you keep saying this. Why is that?
 
  • #13
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That's what I want to say.
Now tell Maxwell was not a good student.
You mixed so many different things... Bohr model has nothing to do with your question, because it's not classical. And you seem to ignore what people write to you...
 
  • #14
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