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Electricity and Magnetism

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Zero Potential Points for Three Charges on a Line

EANDM-P$9W3E

Figure 1 depicts three charges lying along the $\hat{x}$ axis. On the left, at $x = 0$, is a positive charge $q$. In the center, a negative charge, $-2q$ is at the coordinate $x = a$. On the right, a positive charge, $+3q$, is at the coordinate $x = 2a$.

Figure 1. “Timothy Black. Created for Albert.io. Copyright 2016. All rights reserved.”

It

possible for the electric potential to be zero somewhere along the $\hat{x}$ axis in Region I.

It

possible for the electric potential to be zero somewhere along the $\hat{x}$ axis in Region II.

It

possible for the electric potential to be zero somewhere along the $\hat{x}$ axis in Region III.

It

possible for the electric potential to be zero somewhere along the $\hat{x}$ axis in Region IV.