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

[sckeen1988]

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

 

[sckeen1988]

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

 

[vela]

A line charge has a cylindrical symmetry, so apply Gauss's Law using a cylinder as your Gaussian surface.

 

[sckeen1988]

Thanks for the help, forgot to reply at the time due to my astonishment that I had not thought of that.

 

[Nickie]

, as it is not the same as the given electric field value. It is possible that there was an error in the calculation or the given electric field value is incorrect. Please double check the values and equations used to ensure accurate results. Additionally, it is important to note that Gauss' Law for a plane assumes an infinite plane, so the results may not be accurate for a finite length of the line of charge. Further analysis and calculations may be necessary to accurately determine the charge contained in a specific section of the line.