Surface Charge Density and electric field

Thread starter PatrickGeddes
Start date Apr 21, 2012
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Charge Charge density Density Electric Electric field Field Surface Surface charge density

AI Thread Summary

The discussion focuses on calculating the electric field produced by a nonconducting wall with a surface charge density of 8.55 µC/cm² at a distance of 8.55 cm from the wall. The relevant equations include the surface charge density formula and the electric field formula, E = σ/2ε₀. A participant expresses uncertainty about whether the distance from the wall affects the electric field calculation, suggesting a need for clarification on the influence of distance in this context. The consensus indicates that for distances small compared to the wall's dimensions, the electric field can be approximated without significant adjustments for distance. The conversation emphasizes understanding the relationship between surface charge density and electric field strength.

Apr 21, 2012

PatrickGeddes

Homework Statement

A nonconducting wall carries charge with a uniform density of 8.55 µC/cm2.
(a) What is the electric field 8.55 cm in front of the wall if 8.55 cm is small compared with the dimensions of the wall?

Homework Equations

σ= Q/A
E=σ/2Eo

The Attempt at a Solution

E=8.55/2 x 8.854x10^-12

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Apr 21, 2012

PatrickGeddes

Don't think this is right, I feel like the factor that the 8.55cm from the wall should make a difference. Is that right?

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