MCQ
Force between two unit pole strength placed at a distance of one metre is
  • A
    $1 \,N$
  • B
    $\frac{{{{10}^{ - 7}}}}{{4\pi }}\,N$
  • ${10^{ - 7\,}}\,N$
  • D
    $4\pi \times {10^{ - 7}}\,N$

Answer

Correct option: C.
${10^{ - 7\,}}\,N$
c
(c)$F = {10^{ - 7}} \times \frac{{{m^2}}}{{{r^2}}} = \frac{{{{10}^{ - 7}}{{\left( 1 \right)}^2}}}{{{{\left( 1 \right)}^2}}} = {10^{ - 7}}\,N$

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