Electric Potential Over Non-Uniform Rod

AI Thread Summary
The discussion revolves around calculating the electric potential at point P1 due to a thin plastic rod with a nonuniform linear charge density defined as λ = cx. The user attempts to find the potential using the formula v = kc ∫[x/(x+d)]dx from 0 to L but arrives at an incorrect value of -0.17V. Participants suggest that the setup for the integral appears correct but note that the user likely made an error in the integration process. The conversation emphasizes the need for careful integration to accurately determine the electric potential.
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Homework Statement


The thin plastic rod shown in the figure has length L = 18.0 cm and a nonuniform linear charge density λ = cx, where c = 14.5 pC/m2. With V = 0 at infinity, find the electric potential at point P1 on the axis, at distance d = 5.10 cm from one end.

Figure is attached.

Homework Equations


q= \lambda x \\<br /> \lambda = cx \\<br /> dv = (kdq)/r

The Attempt at a Solution


q= \lambda x \\ <br /> dq = \lambda dx \\ <br /> dq = cxdx

I figured you would just use
v =kc \int_{0}^{L}[x/(x+d)]dx
And plug in L, solving for V, in which I get -0.17V, which is flagged as incorrect.

Am I approaching this correctly or is there something I am missing?
 

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The setup for the integral looks okay. You'll have to show details of how you solved the integral.
 
This can be closed, I just integrated incorrectly.
 
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