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 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
- [JEE MAIN 2017]
- 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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- [JEE MAIN 2020]
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