System shown in figure is released from rest. Pulley and spring are massless and the friction is absent everywhere. The speed of $5\, kg$ block, when $2\, kg$ block leaves the contact with ground is : (take force constant of the spring $K = 40\, N/m$ and $g = 10\, m/s^2$)

829-460

  • A

    $\sqrt 2\, m / s$

  • B

    $2\sqrt 2 \,m/s$

  • C

    $2 \,m/s$

  • D

    $4\sqrt 2 \,m/s$

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