Consider a system of three charges $\frac{q}{3},\frac{q}{3}$ and $\frac{-2q}{3}$ placed at points $A,B$ and $C$, respectively, as shown in the figure. Take $O$ to be the centre of the circle of radius $R$ and angle $CAB = 60^o$

824-938

  • A

    The electric field at point $O$ is $\frac{q}{{8\pi {\varepsilon _0}{R^2}}}$ directed along the negative $x-$ axis

  • B

    The potential energy of the system is zero

  • C

    The magnitude of the force between the charges at $C$ and $B$ is $\frac{{{q^2}}}{{54\pi {\varepsilon _0}{R^2}}}$

  • D

    The potential at point $O$ is $\frac{q}{{12\pi {\varepsilon _0}R}}$

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