Two identical tennis balls each having mass $m$ and charge $q$ are suspended from a fixed point by threads of length $l$. What is the equilibrium separation when each thread makes a small angle $\theta$ with the vertical?

  • [JEE MAIN 2021]
  • A

    ${x}=\left(\frac{{q}^{2} l}{2 \pi \varepsilon_{0} {mg}}\right)^{1 / 2}$

  • B

    ${x}=\left(\frac{{q}^{2} l^{2}}{2 \pi \varepsilon_{0} {m}^{2} {g}^{2}}\right)^{1 / 3}$

  • C

    ${x}=\left(\frac{{q}^{2} l}{2 \pi \varepsilon_{0} {mg}}\right)^{1 / 3}$

  • D

    ${x}=\left(\frac{{q}^{2} l^{2}}{2 \pi \varepsilon_{0} {m}^{2} {g}}\right)^{1 / 3}$

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