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
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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.

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Do Rife machines kill viruses and bacteria?

Supporters of the Rife machine claim that virus and bacteria can be killed setting the machine at the right electromagnetic frequency. Rife also reported that a 'beam ray' device of his invention could weaken or destroy the pathogens by…
bart
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Is it possible to pick up radio signals from dental fillings?

I recently heard this claim referred to on House M.D. when the titular character is experiencing phantom sounds, and the show appeared to give the idea some credibility. So I decided to look it up, but only found half hearted explanations or…
John Rhoades
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Are passengers inside cars protected from lightning because of the tires?

It's a common statement that passengers of a car are protected from lightening while inside because the car has rubber tires (which are insulators). An alternative theory often put forward is that the vehicle is made of a metal conductor. The…
Brian M. Hunt
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Do organisms have electromagnetic fields?

I doubt that organisms have electromagnetic (EM) fields. If we did have such a field, then we would certainly be susceptible to having electric currents induced in us by stronger EM fields. Or worse, being affected by magnetic fields like a scrap of…
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Does home-WiFi expose you to less radiation than using the 3G on your cell-phone?

Are there any studies that compare WiFi and cellular data usage, in the home, over time? Mainly I've heard that WiFi uses more battery (so it should emit more radiation) but OTOH it feels like 3G/cellular needs to use higher power to reach the…
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Do tinfoil hats protect against any sort of radiation?

Delusional conspiracy theorists are commonly portrayed as wearing tin-foil hats to protect against mind-control rays from sinister organisations such as [goverments/aliens/NSA/CIA/FBI/liberals/conservatives/devil/god]. Are there any…
terdon
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Does electromagnetic radiation from high energy power installations have negative effects on health?

Note that I'm not asking about high energy RADAR and telecommunications installations or similar systems which can cook small animals alive. I've heard lots of stories about negative health effects of electromagnetic radiation generated by…
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Does the amount of land needed to get the USA to zero-carbon electricity correspond to a small area of Texas?

After watching Elon Musk's presentation regarding the Tesla Powerwall, I had a question. On his diagram of the USA, he claims that a "tiny blue square" on the top of Texas that consists of solar farms would be enough energy to power the united…
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Was an invisible electrostatic wall generated at a plastic tape factory in August 1980?

Amasci.com reported in 1996: David Swenson of 3M Corporation describes an anomaly where workers encountered a strange "invisible wall" in the area under a fast-moving sheet of electrically charged polypropelene film in a factory. This "invisible…
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Do cellphone towers cause health issues?

Yesterday I got a request to install a cellphone tower on my building. The company is going to pay me fair amount but I heard that cell tower radiations cause some serious health issues. Are they safe? Related Questions: Do mobile phones have…
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Do electric heaters with open heating elements "dry the air" or "burn up oxygen"?

There is a popular belief in Russia that electric heaters with an open nichrome heating element (red hot) "burn up oxygen" and "dry the air", unlike oil-filled ones. Is it true that a Joule heater with an open heating element would reduce absolute…
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Does recharging a battery when it is only half-way dead decrease its life span?

One thing many manufactures of laptops and cellphones recommend is that you wait until the battery is completely dead before you recharge it or else it will slowly loose its maximum capacity or have a reduced lifespan. To what extent is this true?…
TheEnigmaMachine
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Do Hubbard Electrometers (E-meters) detect emotion about past experiences?

I saw a table set up for "Free Stress Test" that someone was sitting at looking forlorn because everybody was walking past. I asked how it worked and she got me to sit down with these two cans attached to a device she called an "e-meter" with a…
Hannah
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Is the Kinect IR laser safe?

The Microsoft Kinect uses an IR source (laser or just diode?) to project a pattern in order to get 3D data on what it's looking at. As low-power IR is invisible and intangible, many people have concern about it, implicating it when they feel a…
Nick T
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Is electric muscle stimulation (EMS) training safe and effective?

Electric muscle stimulation (EMS) is touted as having the ability to strengthen muscles, reduce weight, minimize body fat and improve local blood circulation. During physical activity, your brain (inside source) sends a message to nerves to…
Christian
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