Doubt about Electric Field calculations

AI Thread Summary
To calculate the electric field intensity at a distance of 12.9 cm from the axis of a long, straight conductor with a charge density of 1.61 C/m, Gauss's law is applied using the formula E = λ/(2πrε0). The key point of confusion is whether to include the conductor's radius of 3.82 cm in the calculation. It is clarified that the 12.9 cm distance is measured from the axis, making the radius of the conductor irrelevant for this specific calculation. Therefore, only the 12.9 cm should be used in the equation to determine the electric field intensity.
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Homework Statement


Find the magnitude of an electric field intensity at a distance 12.9 cm, from the axis of a long, straight conductor, which has a radius 3.82 cm, and a charge density of 1.61 C/m.

Homework Equations


Gauss's law

The Attempt at a Solution


E= λ/2πrε0

Hello, I'm having some troubles understanding this question. To find E i would simply use the 12.9 cm radius, convert it into meters and use the above equation but if I do so I won't need the other information given of the radius of the conductor.
Do you agree with me? or should I add the 12.9 + the 3.82 radius and put that value into the equation?
thanks
 
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The problem clearly states that the 12.9 cm distance is the distance from the axis. The 3.82 cm information is a red herring.
 
thank you!
 
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