Force between two unit pole strength placed at a distance of one metre is

  • A

    $1 \,N$

  • B

    $\frac{{{{10}^{ - 7}}}}{{4\pi }}\,N$

  • C

    ${10^{ - 7\,}}\,N$

  • D

    $4\pi \times {10^{ - 7}}\,N$

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