A wire of variable mass per unit length $\mu = \mu _0x$ , is hanging from the ceiling as shown in figure. The length of wire is $l_0$ . A small transverse disturbance is produced at its lower end. Find the time after which the disturbance will reach to the other ends

814-667

  • A

    $\sqrt {\frac{{8\,{l_0}}}{g}} $

  • B

    $\sqrt {\frac{{4\,{l_0}}}{g}} $

  • C

    $\sqrt {\frac{{2\,{l_0}}}{g}} $

  • D

    None

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