Two wires of the same material (Young's modulus  $Y$ ) and same length $L$  but radii  $R$  and  $2R$  respectively are joined end to end and a weight  $W$  is suspended from the combination as shown in the figure. The elastic potential energy in the system is

828-314

  • A

    $\frac{{3{W^2}L}}{{4\pi {R^2}Y}}$

  • B

    $\frac{{3{W^2}L}}{{8\pi {R^2}Y}}$

  • C

    $\frac{{5{W^2}L}}{{8\pi {R^2}Y}}$

  • D

    $\frac{{{W^2}L}}{{\pi {R^2}Y}}$

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