MCQ
Two identical blocks are kept on a frictionless horizontal table connected by a spring of stiffness $K$ and of original length $\ell_0$ A total charge $Q$ is distributed on the block such that maximum elongation of sparing at equilibrium is equal to $x$ value of q is:
  • A
    $2\ell_0\sqrt{4\pi\in_0(\ell_0+\text{x})}$
  • B
    $2\text{x}\sqrt{4\pi\in_0\text{k}(\ell_0+\text{x})}$
  • $2(\ell_0+\text{x})\sqrt{4\pi\in_0\text{kx}}$
  • D
    $(\ell_0+\text{x})\sqrt{4\pi\in_0\text{kx}}$

Answer

Correct option: C.
$2(\ell_0+\text{x})\sqrt{4\pi\in_0\text{kx}}$

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