How Much Charge Does a 3cm Section of a Charged Line Hold?

AI Thread Summary
The discussion revolves around calculating the charge contained in a 3cm section of a charged line, given an electric field of 830 N/C at a distance of 0.475m. The initial approach incorrectly applied the formula for an infinite plane instead of a line of charge. The correct method involves using Gauss's Law with a cylindrical Gaussian surface to account for the line charge's cylindrical symmetry. The user acknowledges the error and seeks guidance on the appropriate calculation for a line of charge. The conversation highlights the importance of using the correct formulas in electrostatics.
sckeen1988
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The electric field 0.475m from a very long uniform line of charge is 830 N/C.

How much charge is contained in a section of the line of length 3.00cm?

My solution:
the Electric field from an infinite plane is

E=σ/(2*ε0), so σ=E*ε0*2=1.47*10^-8

3.00cm=.03m

.03*1.47*10^-8=4.41*10^-10

This answer is showing to be wrong
 
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Just realized my problem was that my work was for a plane, not a line of charge. I'm not sure how to solve this for a line of charge though
 
A line charge has a cylindrical symmetry, so apply Gauss's Law using a cylinder as your Gaussian surface.
 
Thanks for the help, forgot to reply at the time due to my astonishment that I had not thought of that.
 

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