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AP® Physics C: E & M

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Charges in a Line

APPHEM-C1ECUE

Two charges are located on the axis shown below. A charge $+3q$ is located at $2R$ from the origin while a charge $–q$ is located at $–R$ from the origin.

Where could a charge of $+7q$ be located in order for the electric field at the origin to equal zero?

A

$R$

B

$-R$

C

$-2R$

D

$-4R$

E

$-6R$