V Due To Infinite Line of Point Charges

Kajayacht
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Homework Statement


An infinite number of point positive charges of 2.0 C each are arranged in the following linear configuration with a = 88 cm. Find the electric potential at the point 0 on the scale.

(link to image)
http://img232.imageshack.us/i/prob02.gif/

[URL]http://img232.imageshack.us/i/prob02.gif/[/URL]

Homework Equations



Sum of Geometric Series
S = a / (1-r)
Electric Potential
V = k*q / r

The Attempt at a Solution



S = .88 / (1-.5)
S = 1.76 m

V = 8.989e9 * 2 C / 1.76 m
V = 1.021 V which is wrong.

Any ideas what I'm doing wrong?
 
Last edited by a moderator:
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Nevermind, this should be in introductory physics :S Sorry guys lol
 
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