The mass of the bob of a simple pendulum of length $L$ is $m$. If the bob is left from its horizontal position then the speed of the bob and the tension in the thread in the lowest position of the bob will be respectively

824-560

  • A

    $\sqrt {2gL}$ and $3\,mg$

  • B

    $3\,mg$ and $\sqrt {2gL}$

  • C

    $2\,mg$ and $\sqrt {2gL}$

  • D

    $3\,gL$ and $3\,mg$

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