Gauss's law on a charged sheet.

AI Thread Summary
The discussion revolves around calculating the electric field produced by a uniformly charged sheet with a charge density of 87 pC/m². The user initially calculated the electric field using Gauss's law, arriving at a value of 4.92 N/C. However, this value differs significantly from the book's answer of 49 kN/C. Participants suggest that the discrepancy may stem from a misunderstanding of the charge density units, proposing that the charge density should be in pC/cm² rather than pC/m². Clarifying the units is essential for resolving the calculation error.
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Homework Statement



find the field produced by a uniformly charged sheet carrying 87 pC/m2

Homework Equations



\oint \vec{E}.d\vec{A} = qenclosed/\epsilon

The Attempt at a Solution



\Phi= \sigmaA/\epsilon
\Phi=\oint E.dA = ## E(2A) ##

2EA= \sigmaA/\epsilon
E = \sigma/(2\epsilon) = 4.92 N/C where I use 8.85*10-12 for \epsilon (this has been the value used through the book)
However the book says the answer is 49 kN/C
could someone point out my error? Thanks.
 
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Your answer looks OK to me. What book are you using?
 
Since you are off (from the book's answer) by 104, I wonder if the charge density was meant to be in pC/cm2, not pC/m2.
 
I'm using Richard Wolfson's: essential university physics 2nd edition, ch 21 qn 33.
 
yeah that might be the problem, as i have seen similar qns to this one online but they use pC/cm^2 instead of pC/m^2
 

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