Electric field

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In physics, the space surrounding an electric charge or in the presence of a time-varying magnetic field has a property called an electric field. This electric field exerts a force on other electrically charged objects. The concept of an electric field was introduced by Michael Faraday.

The electric field is a vector field with SI units of newtons per coulomb (N C−1) or, equivalently, volts per metre (V m−1). The SI base units of the electric field are kg·m·s−3·A−1. The strength of the field at a given point is defined as the force that would be exerted on a positive test charge of +1 coulomb placed at that point; the direction of the field is given by the direction of that force. Electric fields contain electrical energy with energy density proportional to the square of the field intensity. The electric field is to charge as gravitational acceleration is to mass and force density is to volume.

A moving charge has not just an electric field but also a magnetic field, and in general the electric and magnetic fields are not completely separate phenomena; what one observer perceives as an electric field, another observer in a different frame of reference perceives as a mixture of electric and magnetic fields. For this reason, one speaks of "electromagnetism" or "electromagnetic fields." In quantum mechanics, disturbances in the electromagnetic fields are called photons, and the energy of photons is quantized.

For more information about Electric field, read the full article at Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.


News tagged with electric field

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Broadband invisibility in the microwave range

Physics / General Physics

created Sep 11, 2009 | popularity 3.9 / 5 (10) | comments 1

(PhysOrg.com) -- In the series Star Trek, Klingons and Romulans have spaceships outfitted with cloaking devices that hide their presence from sight, as well as from the sensors of their rivals' spaceships. Unlike current invisi ...


3D nanotube assembly technique for nanoscale electronics

3D nanotube assembly technique for nanoscale electronics

Nanotechnology / Nanophysics

created Oct 22, 2008 | popularity 4.7 / 5 (41) | comments 0

(PhysOrg.com) -- For the past several years, researchers have been trying to take advantage of carbon nanotubes’ good electrical properties for future nanoscale electronics applications. One of the biggest ...


Scientists discover giant Rydberg atom molecules

Physics / Condensed Matter

created Jun 24, 2009 | popularity 4.4 / 5 (12) | comments 4

A group of University of Oklahoma researchers led by Dr. James P. Shaffer, Homer L. Dodge Department of Physics and Astronomy, have discovered giant Rydberg molecules with a bond as large as a red blood cell. Determining ...


Multiferroics -- making a switch the electric way

Electric Switches Hold Promise for Data Storage

Physics / General Physics

created May 22, 2009 | popularity 4.5 / 5 (8) | comments 1

(PhysOrg.com) -- Multiferroics are materials in which unique combinations of electric and magnetic properties can simultaneously coexist. They are potential cornerstones in future magnetic data storage and ...


Brown researchers create novel technique to sequence human genome

Researchers create novel nanotechnique to sequence human genome

Nanotechnology / Bio & Medicine

created Apr 15, 2009 | popularity 5 / 5 (3) | comments 2

Since the human genome was sequenced six years ago, the cost of producing a high-quality genome sequence has dropped precipitously. More recently, the National Institutes of Health called for cutting the cost ...


Multiferroic compounds used to produce smaller and cheaper digital memories

Multiferroic compounds used to produce smaller and cheaper digital memories

Physics / Condensed Matter

created Nov 27, 2009 | popularity 4.7 / 5 (6) | comments 1

(PhysOrg.com) -- Is it possible to make even more compact digital memories for portable electronic devices and which consume even less energy? A team of French researchers has recently demonstrated that it ...


Opposites attract - but they may not stay together

Opposites attract -- but they may not stay together

Physics / General Physics

created Sep 24, 2009 | popularity 4.7 / 5 (6) | comments 1

(PhysOrg.com) -- Opposites may always attract. But they may not remain together long-term. In a counter-intuitive discovery published in the current edition of the journal Nature, researchers from Harvard, the Un ...


Scientists Use High-energy Particles from Space to Probe Thunderstorms

Space & Earth / Earth Sciences

created Jun 01, 2009 | popularity 4.4 / 5 (7) | comments 2

(PhysOrg.com) -- Florida Institute of Technology researchers are trying to solve one of the great mysteries in nature: how thunderstorms make lightning. Because, in principle, lightning is a big spark it should behave like ...


Sensor Detects Onset of Acute Myocardial Ischemia

Physics / Soft Matter

created Apr 23, 2009 | popularity 5 / 5 (1) | comments 1

(PhysOrg.com) -- Engineering researchers at the University of Arkansas have fabricated and tested a unique biosensor that measures concentrations of potassium and hydrogen ions in the human heart with high specificity. The ...


Silicon superlattices: New waves in thermoelectricity

Nanotechnology / Nanophysics

created Apr 01, 2009 | popularity 3.7 / 5 (7) | comments 1

(PhysOrg.com) -- A University of Wisconsin-Madison research team has developed a new method for using nanoscale silicon that could improve devices that convert thermal energy into electrical energy.


Spanish scientists confirm the existence of electric activity in Titan

Space & Earth / Astronomy

created Oct 22, 2008 | popularity 4.4 / 5 (18) | comments 1

Physicists of the University of Granada and the University of Valencia (Spain) have developed a proceeding to analyse specific data sent by the Huygens probe from Titan, the largest moon of Saturn, proving "in an unequivocal ...


Killer pulses help characterize special surfaces

Physics / General Physics

created Jul 29, 2008 | popularity 4.8 / 5 (4) | comments 0

Detecting deadly fumes in subways, toxic gases in chemical spills, and hidden explosives in baggage is becoming easier and more efficient with a measurement technique called surface-enhanced Raman scattering. To further improve ...


Shimmering ferroelectric domains

Shimmering ferroelectric domains

Physics / General Physics

created Jul 18, 2008 | popularity 4.6 / 5 (14) | comments 2

Ferroelectric materials are named after ferromagnetic ones because they behave in a similar way. The main difference: these materials are not magnetic, but permanently electrically polarized. They have great ...


Scientists close in on source of X-rays in lightning

Space & Earth / Earth Sciences

created Jul 15, 2008 | popularity 4.4 / 5 (13) | comments 0

University of Florida and Florida Institute of Technology engineering researchers have narrowed the search for the source of X-rays emitted by lightning, a feat that could one day help predict where lightning will strike.