What is the electric potential midway between the two charges?

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The discussion centers on calculating the electric potential midway between two equal positive charges of +2.0 µC, which are 3.0 cm apart. The user seeks clarification on the origin of certain numbers in their calculations, specifically the factor of 2 before the constant K and the distance r being 1.5 x 10^-2 m. It is explained that the factor of 2 arises from summing the contributions from both charges, while r is half the distance between the charges. The equation used is kq/r, with adjustments for both charges leading to the simplified form 2kq/r. Understanding these components is essential for accurately determining the electric potential and electric field at the midpoint.
sasuke07
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Homework Statement


Consider two equal positive charges (q=+2.0 µC) a distance of 3.0 cm apart. What is the electric potential midway between the two charges? What is the E field at this point?

I got the work and everything all solved out, i just don't know where some of the numbers came from. Where does the 2 before K come from, I understant the q= 2X10^-6, but why is r 1.5x10^-2? I am just wondering where some of the numbers came from.

Homework Equations


kq/r=E


The Attempt at a Solution


look at attachment
 

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hi sasuke07! :smile:
sasuke07 said:
Where does the 2 before K come from, I understant the q= 2X10^-6, but why is r 1.5x10^-2? I am just wondering where some of the numbers came from.

that equation is kqL/rL + kqL/rL = 2kq/r …

they're defining qR = qL = q and rR = rL = r :wink:​

(and r is half of 3.0 cm)
 

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