- Speed of electricity
The Speed of electricity refers to the relatively slow movement of free
electrons orion s through a conductor in the presence of anelectric field , also known asdrift velocity . It is often confused with the propagation speed of anelectromagnetic wave . It is the electromagnetic wave that can carry information (data ), not the movement of electrons.Free electrons in a conductor vibrate randomly, but without the presence of an electric field there is no net velocity. When a
DC voltage is applied the electrons will increase in speed proportional to the strength of the electric field. These speeds are on the order of millimeters per second.AC voltages cause no net movement; the electrons "wiggle" back and forth in response to the alternating electric field.In contrast, electromagnetic wave propagation is much faster, and depends on the dielectric constant of the material. In a vacuum the wave travels at the
speed of light and almost that fast in air. Propagation speed in a copper conductor is about 99.9% the speed of lightFact|date=November 2007.ee also
*
Drift velocity
*Velocity of propagation
*Speed of Light External links
* [http://www.ultracad.com/articles/propagationtime.pdf Propagation Times]
* [http://www.cartage.org.lb/en/themes/sciences/physics/Electromagnetism/Electrostatics/ElectricCurrent/Mysteryofelectric/Mysteryofelectric.htm Speed of Electricity]
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