Electric field expression problem

AI Thread Summary
The problem involves calculating the electric field at point P, located a distance x from one end of a thin rod of length L with total charge Q aligned along the y-axis. The electric field components are derived from integrating the contributions of small charge elements along the rod. The x-component is calculated using the limits from 0 to L, while the y-component requires determining the appropriate limits for integration, which also range from 0 to L. The expressions for the electric field components involve trigonometric functions of the angle theta formed between the line connecting the charge element to point P and the rod itself. The discussion emphasizes the need for clarity in setting integration limits for both components to accurately solve the problem.
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So here is the problem, there is thin rod of length L with total charge Q. The rod was placed so it is along the y-axis. From the rod a distance x is point P

Homework Statement


Find an expression for the electric fields E at distance x from the end of the rod. Give your answer in component form


Homework Equations


F= qE
Delta Q= Lambda* Delta L (linearly charged density)
E= integrate of delta E


The Attempt at a Solution


I integrate and found the x-component of the electric fields but haven't been able to figure the y-component...I'm not sure what is the limit for the y-component (my limit for x-component was 0 to L)

Thanks for all the helps
 
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In this problem point P is fixed at a distance x from one end of the rod.
Consider a small element dl on the rod. Charge on it will be Q/L*dl. Line joining P and dl make an angle theta with the rod. Due to this element field at P is given by
dE = k*Q/L*dl/(x*2 + l*2)
Its x-component is dE*sin(theta) = dE*x/(x^2 + l^2)^1/2 and limit will be 0 to L
Its y-component is dE*cos(theta) = dE*l/(x^2 + l^2)^1/2 and limit will be 0 to L
 
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