Capacitor: Difference between revisions

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Electric field near the center of a two-plate capacitor
Electric field near the center of a two-plate capacitor
   
   
<math>\ E=\frac{Q/A}{epilson_0}</math> One plate has charge <math>\ +Q</math> and other plate has charge <math>\ -Q</math>;  each plate has area A; Direction is perpendicular to the plates. Assumption: separation between capacitor is very small compared to the area of a plate.
<math>\ E=\frac{Q/A}{epilson_0}</math> One plate has charge <math>\ +Q</math> and other plate has charge <math>\ -Q</math>;  each plate has area A; Direction is perpendicular to the plates. Assumption: separation between capacitor is very small compared to the area of a plate.


Fringe Field (just outside the plates near center of disk)
Fringe Field (just outside the plates near center of disk)


<math>\ E_{fringe}=\frac{Q/A}{2epilson_0}\frac{s}{R}</math> <math>\ s</math> is the separation between plates; <math>\ R</math> is the radius of plate
<math>\ E_{fringe}=\frac{Q/A}{2epilson_0}\frac{s}{R}</math> <math>\ s</math> is the separation between plates; <math>\ R</math> is the radius of plate


==Examples==
==Examples==

Revision as of 23:42, 18 November 2015

Short Description of Topic

Claimed by Jiwon Yom

This page is all about the Electric Field due to a Point Charge.

Electric Field

Electric Field of two uniformly charged disks: A Capacitor

The Electric Field of a Capacitor can be found by the formula:

Electric field near the center of a two-plate capacitor


[math]\displaystyle{ \ E=\frac{Q/A}{epilson_0} }[/math] One plate has charge [math]\displaystyle{ \ +Q }[/math] and other plate has charge [math]\displaystyle{ \ -Q }[/math]; each plate has area A; Direction is perpendicular to the plates. Assumption: separation between capacitor is very small compared to the area of a plate.

Fringe Field (just outside the plates near center of disk)


[math]\displaystyle{ \ E_{fringe}=\frac{Q/A}{2epilson_0}\frac{s}{R} }[/math] [math]\displaystyle{ \ s }[/math] is the separation between plates; [math]\displaystyle{ \ R }[/math] is the radius of plate

Examples