$A$ body of mass $m = 10^{-2} \ kg$ is moving in a medium and experiences a frictional force $F = -kv^2$. Its initial speed is $v_0 = 10 \ ms^{-1}$. If,after $10 \ s$,its energy is $\frac{1}{8} mv_0^2$,the value of $k$ will be

  • A
    $10^{-3} \ kg \ m^{-1}$
  • B
    $10^{-3} \ kg \ s^{-1}$
  • C
    $10^{-4} \ kg \ m^{-1}$
  • D
    $10^{-1} \ kg \ m^{-1} \ s^{-1}$

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