All Questions
40
questions
0
votes
4
answers
129
views
Why should an electron falling into the nucleus, according to the Maxwell's laws of electrodynamics, destroy the atom?
It is often said in physics and chemistry classes and textbooks that atoms must be unstable when the electron continuously loses energy and finally fall into the nucleus according to classical physics....
3
votes
2
answers
129
views
Radiation from accelerated charged in a co-accelerated reference frame
I was wondering if I sit on a accelerated charge particle I will not observe radiation since the particle is at rest according to me. But my friend observes it from outside and he will see radiation ...
0
votes
1
answer
67
views
Paradox in the observation of ripple
What I am going to speak about may not be a paradox but i see a contradiction here so I used used the word "paradox". To begin with, let there be 2 charges A and B which are stationary with ...
1
vote
3
answers
112
views
Accelerated Electric Charges
We know that an accelerated electric charge produces electromagnetic radiation.
We also know that acceleration is relative to an observer.
Take electrically neutral observers A and B, who are ...
1
vote
2
answers
164
views
Energy-work theorem and dissipation of energy by an accelerating charge
By the work energy theorem we have that the total energy of a nonrelativistic point charge, $q_0$ of mass $m$, moving in an electric field $\mathbf{E}$ is
$ E = E_k + U_e = \frac{1}{2}mv^2 + q_0V \...
-1
votes
2
answers
65
views
If we vibrate a charged mass, will it radiates or not? [closed]
It is said that electromagnetic radiation created from accelerated charged particle.
I want to mechanically vibrate a charged mass , then will it radiates or not?
1
vote
1
answer
92
views
Intuitive explanation for coefficient in the Larmor formula
So the Larmor formula tells us the total power radiated by an accelerating point charge that doesn't go too fast with respect to the speed of light is $P=\frac{2}{3}\frac{q^2 a^2}{c^3}$ (written in ...
2
votes
2
answers
149
views
Which equations indeed describe moving/accelerated charge field?
The thing that I have not understood completely, for 100%, is how does the field of the electric charge is "updated".
If to consider a frame of reference where the charge is static, does ...
0
votes
0
answers
39
views
Free-falling electron [duplicate]
An electron freely falls in the Earth's gravity, while being enclosed in a cylinder that contains energy detectors. The electron accelerates and therefore radiates energy, which is detected. However, ...
0
votes
1
answer
94
views
Sidney Coleman's argument that a hyperbolically accelerated electron radiates
On page 35 of Sidney Coleman's Classical Electron Theory from a Modern Standpoint, he writes:
If we remember that in Maxwellian dynamics, the radiation field is
given by the difference of the ...
1
vote
0
answers
62
views
How to apply Maxwell's equations to electromagnetic waves? [closed]
You know how antennas work and create EM waves...They oscillate charges which create EM waves
Well I'm not satisfied with that explanation so it would be great if you could use maxwells equation to ...
3
votes
2
answers
1k
views
Why would an orbiting electron lose energy?
Ernest Rutherford proposed that the electrons were orbiting around the nucleus just like planets orbiting around the sun. However, this simple picture defied the laws of physics. Electrons revolving ...
0
votes
2
answers
83
views
Can I shake a charge to illuminate my surroundings?
If I put charge on the tip of a rod and shake it back and forth at the right frequency, can I illuminate my surroundings?
According to my understanding of Maxwell equations this would create EM waves ...
2
votes
0
answers
31
views
Regarding accelerated charges produce electromagnetic waves [duplicate]
I know that accelerating charges produce electromagnetic waves. I do not however understand the main reasoning behind this. Most of my knowledge of this topic is from internet sources and stack ...
2
votes
2
answers
354
views
Is constant acceleration not enough for radiation?
A reference source: Does A Uniformly Accelerating Charge Radiate?
Consider the behavior of a DC current compared to an AC current.
Direct current: has locally fast moving free electrons that ...
1
vote
1
answer
765
views
Classical vs. quantum radiation
There seems to be two forms of radiation process:
"Quantum raditation": radiation during a quantum state change, one photon is emitted.
"Classical radiation": radiation of accelerated charge, a lot ...
1
vote
2
answers
700
views
How exactly do accelerated charges produce electromagnetic waves
So I know that accelerated charges produce changing magnetic fields which in turn produce an electric field, according to Faraday's law.
(Of course keeping in mind that the electric and magnetic ...
7
votes
3
answers
491
views
Are electromagnetic waves only caused by accelerating charges?
Like the title says, are electromagnetic waves only caused by accelerating charges? Are there any other methods for the generation of photons?
If electromagnetic waves are ONLY able to be created by ...
3
votes
1
answer
631
views
Do accelerated moving electrons radiate electromagnetic energy?
Do accelerated moving electrons radiate electromagnetic energy?
Generally speaking, the charge should absorb energy instead of radiating energy in the acceleration stage, and release energy in the ...
1
vote
3
answers
208
views
Would fast oscillating charged object emit light?
If I were able to mechanically oscillate an electrically charged object at frequencies of 430-580 THz, would the object emit light?
1
vote
0
answers
29
views
Do all accelerating charge emit EM radiation? [duplicate]
A nucleus and an electron attract each other, so if they are to remain apart, the energy of the electron’s movement must balance the energy of attraction. However, the laws of physics had previously ...
14
votes
4
answers
11k
views
Why doesn't a charged particle moving with constant velocity produce electromagnetic waves?
A charged particle moving with an acceleration produces electromagnetic waves. Why doesn't a charged particle moving with a constant velocity produce electromagnetic waves? As far I understand, the ...
10
votes
5
answers
6k
views
Why does an accelerated charge radiate away energy?
My textbook says:
"Neils Bohr objected to the idea of an electron orbiting a nucleus in a circular orbit. An electron experiences centripetal acceleration and an accelerated charge radiates away ...
0
votes
3
answers
48
views
What is duration/extent/pattern of electromagnetic radiation at a point after it has passed that point?
Let us say I have an accelerating charge. At each point x,y,z in its path from my understanding there is a transverse electromagnetic wave being radiated (could also be viewed as a photon). The ...
20
votes
2
answers
2k
views
Does an accelerating electric dipole radiate?
For such a simple question I'm finding it remarkably hard to get a definitive answer. Googling has not helped me. Consider an ideal electric dipole that is constant i.e. neither its magnitude nor ...
3
votes
2
answers
384
views
Does accelerating magnet emit radiation?
Just like accelerating charge produces emits radiation, does an accelerating magnet emit electromagnetic radiation?
10
votes
1
answer
952
views
Why does an accelerating neutral object not emit Bremsstrahlung radiation? [duplicate]
It is a well established fact that accelerating charges, positive or negative, emit radiation. Why then does a neutral object made up of equal amounts of positive and negative charge not emit any ...
1
vote
1
answer
107
views
Calculating acceleration of a particle from Radiation Pressure
I am trying to calculate the the acceleration of a particle from radiation pressure, assuming all radiation is absorbed. I got $$\Delta \vec{p} = \frac{\Delta U}{c_0}$$ and the intensity $I_S$=$1367 \ ...
30
votes
3
answers
3k
views
How is the energy loss by an accelerating charge expressed in the equations of motion?
I understand how, and why, an accelerating charge emits radiation, and loses energy in the process, as well as the Larmor formula for the power, and its derivation.
However, in classical mechanics, ...
10
votes
2
answers
584
views
Will a change in reference frame produce light? [duplicate]
Let's say I have a charged particle in front of me. If I start spinning in place, the charged particle will appear accelerated to me from my reference frame. If the laws of physics pertaining to this ...
6
votes
5
answers
2k
views
Does a rotating ring of charge radiate power or not?
The Larmor Formula suggests that the power radiated by an accelerating charge is non zero. But we know that a uniformly charged non-conducting ring rotating about its central axis does not radiate. ...
5
votes
1
answer
545
views
Why do planets not radiate EM waves in their orbits?
Despite being overall near-netural, I would expect the individual electrons and proton to radiate long EM waves as we accelerate around the Sun or rotate around our poles. Is the acceleration so small ...
0
votes
1
answer
281
views
Accelerating electric charge
We know that massive bodies attract gas clouds that become ionized and the resulting acceleration can emit very high energy photons.
In a case where a proton for example is undergoing prolonged ...
9
votes
2
answers
658
views
What is the condition for accelerating charge to radiate?
I was always taught that any accelerating charge produces radiation, but I don't think this condition is sufficient condition. For instance, any free charge on Earth is accelerated due to Earth ...
63
votes
7
answers
12k
views
Does a constantly accelerating charged particle emit EM radiation or not?
The Abraham-Lorentz force gives the recoil force, $\mathbf{F_{rad}}$, back on a charged particle $q$ when it emits electromagnetic radiation. It is given by:
$$\mathbf{F_{rad}} = \frac{q^2}{6\pi \...
13
votes
2
answers
15k
views
Why do accelerating electrons emit radiation?
I know how you can emit light with an alternating current, running back and forth, creating an electric field in addition to the magnetic field.
But why does an electron emit light when it gets ...
107
votes
5
answers
109k
views
How and why do accelerating charges radiate electromagnetic radiation?
Let's consider it case by case:
Case 1: Charged particle is at rest. It has an electric field around it. No problem. That is its property.
Case 2: Charged particle started moving (it's accelerating)....
11
votes
3
answers
4k
views
Why doesn't a charged particle radiate energy in circular motion in a uniform magnetic field?
I have studied in my Physics course that one of the drawbacks of Rutherford's atomic model was that when an electron will revolve around the nucleus, it is undergoing acceleration and so it should ...
11
votes
2
answers
1k
views
Is it true that any system of accelerating charges will radiate?
I was recently told by a physics teacher that "any system of charges in which at least some of the charges are executing some sort of accelerated motion, will radiate and lose energy". This refers to ...
13
votes
2
answers
3k
views
If you run an electric current through a wire loop, do the accelerated charges radiate?
Does an accelerated charge always radiate?
For example the current electrons in an electric circuit when moving through a turn they are accelerated, do they radiate because of that acceleration?
If ...