Calculus with the electric field

AI Thread Summary
To find the electric field at point P for a line segment of length L, first establish a coordinate system, placing the line along the x-axis with one end at the origin. The electric field contribution from a small line element, dx, can be analyzed using charge density, lambda. Integration of these contributions is necessary to determine the total electric field at point P. Utilizing trigonometric functions, such as sine, helps relate the small section of the conductor to the distance from the point of interest. Understanding these steps is crucial for solving the problem effectively.
pakman2012
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Homework Statement


1. Find the electric field at point P for a line segment with length L. Diagram attached.

Homework Equations



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The Attempt at a Solution



I have next to no clue on how to do this question. My first idea was to try and set up one of the lengths as r, and work from there, but I wasn't able to do anything conclusively. The most confusing part is not being able to do the calculus and relating the variables to fit the purposes of the problem. How exactly do you find the potential of something like this, in general?

Any help for this question will be greatly appreciated.
 

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First pick appropriate coordinate axes. The line along the x-axis and the left end at the origin for example.
Then consider the contribution to E resulting from a small line element dx (with charge density lambda say) and add up (integrate) all the contributions.
 
Galileo said:
First pick appropriate coordinate axes. The line along the x-axis and the left end at the origin for example.
Then consider the contribution to E resulting from a small line element dx (with charge density lambda say) and add up (integrate) all the contributions.

The trick is to use sine to relate the small section of conductor(dx) to the distance from your point.
 
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