As shown in figure, two blocks are connected with a light spring. When spring was at its natural length, velocities are given to them as shown in figure. Choose the wrong alternative.

822-638

  • A

    Velocity of center of mass of the system is $3\, m/s$ (towards right)

  • B

    When spring is maximum compressed velocity of $20\, kg$ block is $3\, m/s$ (towards
    right)

  • C

    When spring is maximum elongated velocity of $10\, kg$ block is $3\, m/s$ (towards
    left)

  • D

    Both $(A)$ and $(C)$

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If two springs $S_1$ and $S_2$ of force constants $k_1$ and $k_2$, respectively, are stretched by the same force, it is found that more work is done on spring $S_1$ than on spring $S_2$.
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