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3
votes
1answer
143 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 ...
0
votes
3answers
39 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
1answer
68 views

Accelerating a Black Hole

I believe I may have seen this question somewhere with the answer I am looking for, but I can't seem to find it here. If that's the case, then this question may be a duplicate. I believe I read that ...
1
vote
0answers
24 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 ...
2
votes
5answers
222 views

Why does an electron not emit energy when it is in a stationary state?

The Bohr's postulate states that an electron does not emit energy when it is in a stationary state. My question is, is it only a postulate or does it have proof? Also on what basis did Bohr come to ...
6
votes
5answers
1k 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 ...
8
votes
4answers
1k 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
3answers
36 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 ...
1
vote
1answer
666 views

Magnet can spin the fidget spinner, Why?

I have noticed that a small neodymium magnet can get my fidget spinner going at a relatively low velocity compared to what I can get from the force of my finger. I think I know why it is possible to ...
10
votes
2answers
556 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 ...
2
votes
2answers
159 views

Does accelerating magnet emit radiation?

Just like accelerating charge produces emits radiation, does an accelerating magnet emit electromagnetic radiation?
9
votes
1answer
635 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
1answer
39 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 \ ...
1
vote
0answers
128 views

Infinite current carrying wire, moving parallel to it's current flow direction?

At $t=0$ current flows in an infinite wire, and creates a magnetic field, after sometime the infinite wire begins to accelerate(only the wire wile $I$ remains constant), in a direction parallel to the ...
1
vote
1answer
96 views

A doubt regarding Lenz's Law

In one of the most common examples of Lenz's Law a magnet is dropped inside a copper tube and due the induced EMF and the eddy currents generated in the copper tube the magnet falls through it with ...
23
votes
3answers
1k 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, ...
0
votes
1answer
52 views

For a charged particle, how many times can you accelerate its acceleration?

A charged particle's acceleration in the electric field of a uniform, simply connected, and three-dimensional charge distribution is changed (getting bigger or smaller depending on the signs of the ...
1
vote
1answer
410 views

How does a charged particle accelerate in an uniform electric field? (Abraham-Lorentz force) [closed]

Suposse we have a charged particle placed in some region with an uniform electric field. It's clear that a force $$\vec F_e =q\vec E $$ will appear on the particle due to Lorentz force. However, the ...
10
votes
2answers
548 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 ...
0
votes
1answer
230 views

Why does time varying magnetic field produce acceleration in a still electron?

This problem is from my textbook exercises. I feel no force can be exerted on an electron unless it is "moving" in a magnetic field. But my textbook's answer key says that the answer is (B). Can ...
4
votes
3answers
890 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. ...
1
vote
1answer
988 views

Alpha Particle moving through a magnetic field [closed]

How would I find the acceleration of an alpha particle moving through a magnetic field given the force of the magnetic field, the charge, the initial velocity and the strength of the magnetic field.
10
votes
2answers
303 views

Charged Accelerometer in Orbit

It is well known that an accelerometer (or any other object for that matter) in a gravitational orbit will register nearly zero acceleration. According to this answer, this is because the object is, ...
5
votes
1answer
384 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 ...
3
votes
1answer
72 views

Velocity of particle constant under null initial magnetic force

I have got a doubt on the exact application of Newton's first, and third, law. Let us for example suppose that a particle, electrically charged with charge $q$, is moving at the instant $t=0$ with ...
5
votes
2answers
491 views

Relativistic explanation of Radiation

I ask this question again in a simpler, shorter form. Maxwell's equations can be derived with Special relativity starting from the Coulomb's law. Therefore all the phenomena of classical ...
4
votes
1answer
218 views

The Inertial theory of Sciama and an electromagnetic analogue

In 1952 D. W. Sciama introduced a paper On the origin of inertia. It presents a method in which inertia could arise from other mass in the universe. It goes along these lines: If you try to ...
3
votes
1answer
136 views

What force decays an oscillating charge?

Consider this scenario: We have a charge on a spring. As it oscillates, it loses energy to radiation. What force decays the oscillation? As far as I can see, the only forces in the scenario are ...
0
votes
0answers
142 views

Gravitomagnetic railgun

Would a gravitomagnetic analogue of a railgun work as expected, in theory? Consider replacing the electric currents on each rail with mass currents. Then place a mass between the rails, moving with ...
2
votes
1answer
3k views

Electrons and Magnetism

Electron at rest generates Electric field. Electron moving without acceleration produces electric and magnetic field. Electron moving with acceleration produces electromagnetic waves. Please explain ...
2
votes
0answers
332 views

Odd experiment results (electromagnetics)

Okay, a bit of background. So I'm working on a linear accelerator (you might know it as a Gauss rifle), and I had worked through the equations I thought I needed (Magnetic force, displacement, etc.) ...
1
vote
3answers
2k views

How does an electron undergoing uniform circular motion exactly lose energy?

One of the main reasons for the failure of the Rutherford model of atomic structure, it is famously stated, is that the electron undergoing circular orbit loses energy since due to its centripetal ...
0
votes
1answer
181 views

If an electron can't go faster than light, how is energy conserved here?

I came across a physics question recently about accelerating electrons with potential differences and it got me wondering. Here is the question that brought the concept to mind. First off, imagine ...
1
vote
2answers
3k views

Why would an electron in an orbit be accelerating continuously and would thus radiate away its energy and fall into the nucleus in a classical model? [duplicate]

I was reading this answer by madame anna v: You are right, the planetary model of the atom does not make sense when one considers the electromagnetic forces involved. The electron in an orbit is ...
9
votes
2answers
557 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 ...
49
votes
6answers
8k 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 \...
11
votes
2answers
12k 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 ...
53
votes
4answers
61k 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
3answers
824 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 ...
12
votes
2answers
2k 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 ...