Skip to main content

Questions tagged [electromagnetism]

For questions about Electromagnetism - a branch of Physics involving the study of the electromagnetic force, a physical interaction that occurs between electrically charged particles

Filter by
Sorted by
Tagged with
0 votes
0 answers
28 views

How did "Gauss's law" get its name?

Did Carl Friedrich Gauss derive Gauss's law? How did the Maxwell equation we call "Gauss's law" become known as that? In class, we went over how you derive it from Coulomb's law, but I don't ...
Dominic Stewart-Guido's user avatar
0 votes
0 answers
35 views

References on the history of electromagnetism

I am looking for complete and trustable references on the history of electromagnetism. Does anyone have some good recommendations?
Léo Vacher's user avatar
1 vote
0 answers
111 views

Relationship between electromagnetic and topological invariant

I read 17 equations that changed the world by Ian Stewart. This book provides information about the correlation between electromagnetic force and topological invariant. The idea of a topological ...
user1274233's user avatar
1 vote
1 answer
104 views

Black body radiation before Hertz's observation?

From the timeline of Maxwell's prediction 1865 and Hertz's observation in 1887 that gave an understanding of the light wave as EM wave, How did the Black body radiation study understand the emitted ...
Kanokpon Arm's user avatar
2 votes
1 answer
201 views

What was the reason Einstein included reflection from a moving mirror in his relativity paper?

Einstein, in his 1905 relativity paper Electrodynamics of Moving Bodies, allocates a section to the issue of reflection of light from a moving mirror and derives three formulas (angle, frequency, ...
Maesumi's user avatar
  • 133
2 votes
0 answers
83 views

What was defined first and how? The ampere or the vacuum permeability?

I've been looking up the history and evolution of the seven base units and am currently checking out the ampere. What I've found is that 1A is defined as the current in a wire which would experience a ...
SpectraXCD's user avatar
1 vote
4 answers
211 views

Is there a concise but detailed history of electricity?

I have recently become fascinated by the history of electricity. I have researched and come up with the following observations: Static electricity was discovered in early times, by phenomena such as ...
Fraser's user avatar
  • 11
3 votes
2 answers
133 views

Who postulated the first Lagrangian for electrodynamics?

I am trying to find who first translated Maxwell's equations and Lorentz's force into the Lagrangian formalism. It seems a very straightforward thing to do if you know enough of electromagnetism and ...
Mauricio's user avatar
  • 3,907
0 votes
0 answers
54 views

Tesla tried to replicate Hertz's experiment?

Jan Rak, in his NAMI-tech SEM 2023 lecture (@12:53), claims: However, at the time Nicola Tesla […] was trying to replicate the Hertz experiment, and he was unsuccessful. He discovered some other ...
Geremia's user avatar
  • 5,329
0 votes
0 answers
60 views

Translation of Cabeo's Philosophia magnetica

Is there a translation of Niccolò Cabeo's work Philosophia magnetica into English (or other modern language)? The original text in Latin is available for example here but I can't find any translation (...
maxbo's user avatar
  • 1
3 votes
1 answer
130 views

"Équation de Maxwell-Thomson"

In French, Gauss' law for magnetism (no magnetic monopoles) is, sometimes at least, referred to as Équation de Maxwell-Thomson. What is the historical justification of this?
John's user avatar
  • 33
3 votes
0 answers
167 views

Question on Gauss's geometric interpretation of "spherical functions"

In the physics chapter of his biography of Gauss, W.K. Buhler writes the following: Expansions into series are frequent and important in potential theory. So it does not come as a surprise that ...
user2554's user avatar
  • 4,419
0 votes
0 answers
30 views

Early sources for surface and bound charges in polarization

I am looking for early sources (references) to the analysis in electrostatics where the polarization vector is rewritten in terms of bound charges and a surface polarization charge. In terms of what I ...
LDM's user avatar
  • 1
5 votes
1 answer
101 views

How and by whom was the magnetic term in the Hamiltonian first derived?

The Hamiltonian of a charged particle in a magnetic field is: $$H=\frac{1}{2m}(\frac{h}{2\pi i}\nabla-qA)^2+q\phi$$ Can anybody help me find out when, how and by whom was it first derived?
Aida Lf's user avatar
  • 51
3 votes
1 answer
122 views

Why did Maxwell predict radiation pressure?

I know that Kepler thought based on comet tail that light might exert pressure (although is the Solar wind not also involved?) but did Maxwell's prediction stem from newer observations or from perhaps ...
releseabe's user avatar
  • 1,151
0 votes
0 answers
33 views

Granville Wood's Telegraph -- do we know the data rate and range?

I realize this is more a history of engineering question but I do not see a SE devoted to this so I thought I would ask here. https://suiter.com/granville-woods-railway-telegraphy-patent-no-373383/ ...
releseabe's user avatar
  • 1,151
1 vote
0 answers
102 views

A question concerning the history of Maxwell's equations

So I am writing my thesis around the Maxwell equations, in one part I saw to speak about their history. The issue is, I found conflicting pieces of information as to who enunciated the laws first. Let'...
الفقير للعفو's user avatar
1 vote
0 answers
146 views

When were the foundations of vector calculus laid?

Upon some browsing I find from many online sources that vector calculus was created in the time of late 19th century by Gibbs and Heaviside, but Gauss, Green, Stokes, etc., who lived much before that, ...
nickbros123's user avatar
0 votes
1 answer
69 views

What are the equations of Electric Gravity Lorentz derived, and what is the paper in which they are found?

I read on a blogpost that Lorentz built a mathematical model of gravity, but with an assumption that it arose from electrical origins. I tried googling for more information and could not find anything ...
Hisham's user avatar
  • 429
2 votes
1 answer
612 views

The etymology of "radio waves"

The word "radio" originates from "radius", which in turn came from "ray". That's why "radius" means any line from a central focal point to any directions. ...
Piinhuann Chew's user avatar
0 votes
1 answer
141 views

Who gave right hand thumb rule for circular loop of current conducting wire?

To find magnetic field due to current conducting straight wire we have Maxwell's Right hand thumb rule, Which says "Put your right hand thumb in the direction of current then curled fingers shows ...
Level1's user avatar
  • 1
2 votes
0 answers
129 views

Why was the idea of "field" introduced?

I read in my Physics textbook that the notion of Electric fields are useful "when we have to deal with time dependent Electromagnetic phenomenon since no information can travel faster than light&...
Ankit's user avatar
  • 129
0 votes
1 answer
331 views

Component form of the fourth Maxwell's equation

I am doing an introduction to Maxwell's equations, and it is said that originally the equations were in component form. Can anyone help with the derivation of the fourth equation? I have checked many ...
Chaperone's user avatar
3 votes
0 answers
226 views

How did Gauss come up with his law?

Why did it seem at the time of Gauss that the quantity we get by multiplication of electric field with the area would have some value to it? That is what was the motivation for Gauss to find the flux ...
GedankenExperimentalist's user avatar
3 votes
0 answers
126 views

Did Maxwell discuss charge quantization?

I once read in Wikipedia that James Clerk Maxwell included the possibility that charge could be both quantified and continuous. Since the electron hadn't been discovered in 1873, does Maxwell discuss ...
David Jonsson's user avatar
2 votes
0 answers
278 views

Was Nikola Tesla aware of Maxwell's equations?

Was Nikola Tesla aware of Maxwell's equations or Heinrich Hertz's experimental proof of the former when he worked on his radio device invention?
Hans's user avatar
  • 121
2 votes
2 answers
493 views

How were the values of permeability and permittivity derived?

Do you know how the values were measured and if they where determined by particular conditions/ restraints? They can be put to 1 (or to any values, I suppose); what escapes me is why 1/ε × μ must be ...
user157860's user avatar
2 votes
1 answer
161 views

How has the modelling of classical electrodynamics changed since Maxwell?

Maxwell published his Treatise on Electricity and Magnetism in 1873, 150 years ago; before the discovery of quantized charges, special relativity, quantum field theory etc. How has the mathematical ...
Larry Harson's user avatar
3 votes
1 answer
994 views

Why is electric potential denoted by $\phi$?

I haven't found any explanation for it, and I'm curious.
EB97's user avatar
  • 139
0 votes
1 answer
138 views

Notation of Poynting vector

I know that the Poynting vector is defined as the cross-product $\vec{E}\times\vec{H}$ and that is "usually" denoted by $\vec{S}$ or $\vec{N}$. I wonder if there is a particular reason for ...
aghin00's user avatar
0 votes
1 answer
96 views

Did Hertz discover the concept of frequency and if so, how did Doppler think of frequency?

I may not be understanding what a "Hertz" is but it seems to simply be one cycle per second. But would not Doppler have understood what frequency was decades before Hertz? Or was Hertz just ...
releseabe's user avatar
  • 1,151
3 votes
1 answer
210 views

Had Albert Einstein tried to use the Galilean transformation on Maxwell's equations before AE's Special Theory?

I am looking for what motivated Albert Einstein in the direction of his Special Theory. I have read that it is unclear if he was set on that path by the Michelson-Morley experiments. Was AE aware ...
goedelite's user avatar
5 votes
1 answer
108 views

Whatever happened to parageometrical optics of diffraction?

In 1950, Giuliano Toraldo di Francia published a paper [1] with the title "Parageometrical Optics" followed by several other papers on the subject, I dare say culminating in a beautiful ...
hyportnex's user avatar
  • 347
3 votes
0 answers
69 views

Why is the magnetic force on a current-carrying wire sometimes called the Laplace force?

Educated in the UK, I've been used to calling the force on a current-carrying wire in a magnetic field 'the motor effect force'. But I'm increasingly aware of another (less clumsy?) name for it: 'the ...
Philip Wood's user avatar
3 votes
1 answer
230 views

Demystifying Nikola Tesla: Scientifically sound, historically accurate biography

As any physicist knows, a lot of amateur science afficionados out there bring up Nikola Tesla in rather fantastical ways. There are indeed a few reasons for his near mythical status in popular culture,...
Ben's user avatar
  • 133
0 votes
0 answers
64 views

How was it determined that charge and current were made of the same stuff?

Even in my earliest physics course we took for granted that charges are made of electrons (or their absence) and currents are due to the motion of electrons. But the electron is a very modern concept ...
Diffycue's user avatar
  • 109
1 vote
1 answer
334 views

Who discovered the electric potential?

Wikipedia says that the magnetic vector potential was discovered by Neumann in 1845, by Weber in 1846 and Lord Kelvin in 1847. It does not mention who discovered the electric scalar potential. Hence ...
Mozibur Ullah's user avatar
3 votes
1 answer
195 views

de Broglie's conception of the electron

I've been working on de Broglie's thesis (English PDF, Original French PDF) for a course, and I've found something that's been bothering me. My training is in Physics, and so I'm not particularly ...
Philip's user avatar
  • 131
0 votes
0 answers
49 views

Which scientist(s) first measured the elementary charge and how did they do it? [duplicate]

I would be grateful if anyone could shed some light on these questions. Which scientist(s) first measured the elementary charge? If it wasn't measured in a straightforward experimental setting, and ...
alghazali's user avatar
5 votes
2 answers
1k views

How did Stern or Gerlach, of Stern-Gerlach experiment, create individual silver atoms? How were they accelerated?

How, a century ago, could Stern and/or Gerlach KNOW that they had created single silver atoms? How were they moved, or accelerated?
Kurt Hikes's user avatar
3 votes
1 answer
249 views

Bohr-Kramers-Slater (BKS) theory and energy conservation only on statistically basis

I was reading Wikipedia article on Bohr-Kramers-Slater (BKS) theory, https://en.wikipedia.org/wiki/BKS_theory. I encountered two interesting points and need your help to understand the reasons behind ...
PG1995's user avatar
  • 377
5 votes
0 answers
266 views

Were there any contributions to thermodynamics and electromagnetism from Medieval Islamic science?

The Medieval Islamic world, between 8th to the mid 13th century, is known for its developments in academic knowledge. Particularly in astronomy. Many stellar objects still derive their name from ...
Mauricio's user avatar
  • 3,907
0 votes
0 answers
142 views

How did Gauss, Ampere and Biot-Savart derive their laws?

Gauss' law for electricity and magnetism, Ampere's law and Biot-Savart's law — all of these laws are crucial for understanding electromagnetism and Maxwell's equations. But I want to know how each of ...
AYM Shahriar Rahman's user avatar
2 votes
1 answer
143 views

When was the earliest speculation that gravity and electromagnetism had a unified description?

In 1786, Coulomb announced his law that showed that the electromagnetic force between two charged sources followed an inverse square law. Given that gravity followed a similar law, did anyone suggest ...
Mozibur Ullah's user avatar
1 vote
1 answer
152 views

Why is the constant of magnetic fields called permeability and that of electric fields called permittivity? [closed]

Basically the title, I found it weird that we use two different names for each fields. What were the reasons for doing so, historically speaking?
user avatar
5 votes
1 answer
283 views

When was "Faraday's Law of Induction" first expressed in a quantified form?

An often used definition of "Faraday's Law of Induction" goes something like this (found in Wikipedia) The electromotive force around a closed path is equal to the negative of the time rate ...
Math Keeps Me Busy's user avatar
1 vote
0 answers
81 views

Validity of Maxwell's equations in the aether's reference frame

If Maxwell's equations were experimentally found on Earth such as Faradays law, coulombs law , and worked in the Earth's frame of reference, then why did people believe them to be valid in the aether'...
Kashmiri's user avatar
  • 183
2 votes
0 answers
37 views

Who invented the quadrupole lens for charged particles?

I am wondering who actually invented the (magnetic) quadrupole lens or who used it for the first time. I have found some papers from the 50s and 60s about more complicated systems based on Quadrupoles,...
Felix Kern's user avatar
3 votes
1 answer
145 views

Why is wave guide theory developed so long after Maxwell's work was published?

When some fundamental new theory is published, derived work will be done "instantly", example from quantum mechanics: 1926 Schrödinger equation 1927 The first application of quantum ...
jw_'s user avatar
  • 275
1 vote
0 answers
65 views

What is a Heaviside rational current element?

This terminology seems to be referred to a notion invented in an old book of Oliver Heaviside [1]. What is it and why the Biot-Savart law is not unique unless it is applied to a Heaviside rational ...
8cold8hot's user avatar
  • 111