An electron initially at rest, is accelerated through a potential difference of $ 200$  volt, so that it acquires a velocity $8.4 \times {10^6}m/s.$ The value of $e/m$ of electron will be

  • A

    $2.76 \times {10^{12}}C/kg$

  • B

    $1.76 \times {10^{11}}C/kg$

  • C

    $0.76 \times {10^{12}}C/kg$

  • D

    None of these

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