A particle of mass $100\,g$ is projected at time $t =0$ with a speed $20\,ms ^{-1}$ at an angle $45^{\circ}$ to the horizontal as given in the figure. The magnitude of the angular momentum of the particle about the starting point at time $t=2\,s$ is found to be $\sqrt{ K }\,kg\,m ^2 / s$. The value of $K$ is $............$ $\left(\right.$ Take $\left.g =10\,ms ^{-2}\right)$

214475-q

  • [JEE MAIN 2023]
  • A

    $80$

  • B

    $800$

  • C

    $8$

  • D

    $0.8$

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  • [JEE MAIN 2022]

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