Does This Answer Make Sense (basic EM)

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The discussion revolves around the calculation of electric potential and electric field due to a non-uniformly charged plastic rod with charge density λ=cx. The constant c is identified as having units of charge per unit length. There is confusion regarding the limits of integration used in the potential calculation, with the teacher using limits from L to L+1, while the textbook suggests 0 to L. The participant believes the teacher's integration approach is incorrect and seeks clarification on the proper method. The thread highlights the importance of correct integration limits in solving electrostatic problems.
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Homework Statement



The plastic rod of the length L=1 m has a non-uniform charge density λ=cx
where positive constant c =2x10-6 [some unit]. What unit does c have? Find the electric
potential at the point on the x-axis 1 m to the left from the left end of the rod. Find the
electric field at that point as well, preferably via potential.

Homework Equations



V=k*integral(cdx)

The Attempt at a Solution




V=kc*integral(dx)-----V=kcx------V=17980V

Is it just me or is this completely wrong? This is not my solution--it's my teacher and I was under the impression that the integral would end up being (with d=end of rod to point P):

V=kc*integral(x/d+x)-----V=kc[L-d(ln)(1+L/d)]

He ttok his limits of integration as L to L+1, however, in the book it says it should be from 0 to L (even though that doesn't really affect the answer). It is his integration I do not agree with.

Thanks in advance for any clarification.
 
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