Questions tagged [electromagnetism]

Electromagnetism is the branch of science concerned with the forces that occur between electrically charged particles. Use this tag for anything related to electricity, electrical or magnetic fields (such as microwave radiation), etc.

Electro-Magnetic Force
source

Electromagnetic force is one of the four fundamental interactions in nature, the other three being the strong interaction, the weak interaction and gravitation.

Electromagnetism is the interaction responsible for practically all the phenomena encountered in daily life, with the exception of gravity. Ordinary matter takes its form as a result of intermolecular forces between individual molecules in matter.

Electrons are bound by electromagnetic wave mechanics into orbitals around atomic nuclei to form atoms, which are the building blocks of molecules. This governs the processes involved in chemistry, which arise from interactions between the electrons of neighbouring atoms, which are in turn determined by the interaction between electromagnetic force and the momentum of the electrons.

James Clerk Maxwell
James Clerk Maxwell

Electromagnetism manifests as both electric fields and magnetic fields. Both fields are simply different aspects of electromagnetism, and hence are intrinsically related. Thus, a changing electric field generates a magnetic field; conversely a changing magnetic field generates an electric field. This effect is called electromagnetic induction, and is the basis of operation for electrical generators, induction motors, and transformers.

Electric fields are the cause of several common phenomena, such as electric potential (such as the voltage of a battery) and electric current (such as the flow of electricity through a flashlight). Magnetic fields are the cause of the force associated with magnets.

109 questions
7
votes
1 answer

Is there any reason behind oxygen-free cables?

...other than to make you spend more money, of course. Do oxygen free (99.999% or sometimes even more) cables have any plausible effect on an audio system? What about video systems, and even digital systems (by some miracle?)
Thomas O
  • 11,908
  • 7
  • 53
  • 72
6
votes
3 answers

Is reading household power meters frequently helpful for utility companies?

IBM recently published a case study on "smart" power meters. Those power meters read consumption data many times a day and record that data so that it can be analyzed. IBM claims [cool stuff]Giving consumers more visibility into their energy…
sharptooth
  • 1,891
  • 1
  • 14
  • 16
6
votes
1 answer

Does using BlueTooth devices cause leakage of the blood-brain barrier?

In 2012, the EMFacts Consultancy blog quoted Cindy Sage as saying: People should realize that Bluetooth devices that fit in or around the ear typically radiate at 0.23 watts per kilogram (W/Kg). [...] you’ll find the Bluetooth devices are actually…
Nisba
  • 161
  • 4
6
votes
2 answers

Death by electroshock from 12V battery

A solar power book makes this claim: A low voltage system can cause major problems simply because of the huge current that a 12v battery can generate: in excess of 1,000 amps in short burst can easily cause a severe shock -- and even death of…
Fizz
  • 57,051
  • 18
  • 175
  • 291
6
votes
1 answer

Can humans "feel" the earth's magnetic field?

Someone told me that human cells can somehow feel the earth's magnetic field. The same guy thought that centrioles are probably involved. Is it true? If not, would it be true for stronger magnetic fields? It seems that this claim is quite widespread…
Remi.b
  • 2,001
  • 1
  • 17
  • 29
6
votes
2 answers

Can getting in and out of a vehicle at a gas station cause combustion?

The warning signs at gas stations warn that you ought not enter and exit your vehicle while filling up your tank at the gas station. I have also been told by many people that doing so runs a risk of igniting the fuel or making your vehicle…
asteri
  • 531
  • 3
  • 11
5
votes
1 answer

Will the Sun's magnetic activity disrupt electronics on Earth?

I recently came across a claim that the earth's geomagnetism will change and all the electronics devices will be disrupted due to the Sun's magnetic pole change, as described in this video. Additionally, the claim is that all electronics on earth…
5
votes
0 answers

Do electronic bug repellers work?

Possible Duplicate: Ultrasound pest control devices Do electric insect repellers example work? For context, I live in a rented house that has several of these installed. My personal observation is that they do nothing to repel bugs, but actually…
5
votes
0 answers

Do antistatic car-straps reduce static shocks from cars?

There is a line of anti-static rubber straps sold for cars which attach to the chassis of the car and dangle down to the road. It is claimed that they allow static electricity to drain off, preventing mild static shocks. Examples: SCA Anti Static…
Oddthinking
  • 140,378
  • 46
  • 548
  • 638
5
votes
0 answers

Why 'every' electrical devices in an airplane are prohibited during landing and departing?

Possible Duplicate: Are personal electronics a risk to commercial aviation? Not only the electrical devices using EM wave (ex: Cellphone, RC car, ...), but other electrical devices (ex: MP3, Nintendo DS, ...) are also prohibited in airplane, when…
JiminP
  • 151
  • 2
5
votes
0 answers

Is it possible to disable a vehicle with microwave oven magnetron from that distance

In a well-known Youtube channel there is a scene where a scooter had some kind of short circuit caused by magnetron used as a weapon from a distance. I never saw this channel to have fakes but one guy does not believe, saying: OK, rough…
Nakilon
  • 153
  • 7
5
votes
0 answers

Do watches break very often for some people?

I know of someone who cannot seem to wear watches without them breaking much quicker than expected. This person was told it is because their body is producing too much electricity and that by putting nail polish on the reverse of the watch to block…
user25840
  • 67
  • 1
5
votes
1 answer

A Boy with the Magnetic body & healing hands, How this is scientifically possible?

Possible Duplicate: Do metal items stick magnetically to “Magnet Boy”? A six-year-old Croatian schoolboy Ivan Stoiljkovic has a magnetic personality and astounds people with his magnetic body. He can stick metallic objects such as spoons,…
Great mailz
4
votes
0 answers

Can electricity be transmitted wirelessly over Zenneck surface waves?

Viziv Technologies claims that they are researching the ability to send and receive electricity using the Zenneck Surface Waves. August 2019 press release Viziv Technologies, LLC, and Baylor University announce a new research partnership aimed at…
Finesser
  • 49
  • 2
4
votes
0 answers

Can StoreDot batteries be charged in two minutes?

CNET writes: StoreDot's system, which you can see in action in the video [at the link], uses a different chemical makeup to traditional batteries. We saw a modified Samsung Galaxy S5 go from 15 percent battery to 100 percent in a little under two…
phact
  • 141
  • 4