How to Calculate the Electric Field Near a Long Charged Wire?

AI Thread Summary
To calculate the electric field near a long charged wire, the discussion emphasizes using Gauss's law when the wire's length is significantly greater than the distance from the point of interest. The relevant equations include E = kq/r^2 and E = kQx/(x^2 + a^2)^(3/2). Initial attempts to solve the problem involved treating the wire as a circle, which was unsuccessful. Ultimately, the user resolved the issue independently. The conversation highlights the importance of selecting the appropriate method for calculating electric fields in different scenarios.
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Homework Statement


Calculate the electric field at a point 2.00 cm perpendicular to the midpoint of a 1.94 m long thin wire carrying a total charge of 4.78 uC.

Hint: You could integrate BUT if the wire is very long compared to the distance from the wire to where you are calculating the electric field, then the electric field will be radial and Gauss's law might be easier.

Homework Equations



E = \frac{kq}{r^2}

where k = 9E9
q = 4.78E-6
r = 0.02 m

E = \frac{kQx}{(x^2 + a^2)^(3/2)}


The Attempt at a Solution



First i tried to use the second formula where i made the wire into a circle and used 0.02m as the radius. That didnt work, so i used gauss's formula as the hint suggests, which also didnt work. Suggestions?
 
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Nevermind, i solved it.
 
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