An electron having charge $1.6 \times {10^{ - 19}}\,C$ and mass $9 \times {10^{ - 31}}\,kg$ is moving with $4 \times {10^6}\,m{s^{ - 1}}$ speed in a magnetic field $2 \times {10^{ - 1}}\,tesla$ in a circular orbit. The force acting on electron and the radius of the circular orbit will be

  • A

    $12.8 \times {10^{ - 13}}\,N,\,1.1 \times {10^{ - 4}}\,m$

  • B

    $1.28 \times {10^{ - 14}}\,N,\,1.1 \times {10^{ - 3}}\,m$

  • C

    $1.28 \times {10^{ - 13}}\,N,\,1.1 \times {10^{ - 3}}\,m$

  • D

    $1.28 \times {10^{ - 13}}\,N,\,1.1 \times {10^{ - 4}}\,m$

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