Two trains travelling on the same track are approaching each other with equal speeds of $40\ m/s$ . The drivers of the trains begin to decelerate simultaneously when they are just $2.0\ km$ apart. Assuming the decelerations to be uniform and equal, the value of the deceleration to barely avoid collision should be..........$m/s^2$

  • A

    $11.8$

  • B

    $11$

  • C

    $2.1$

  • D

    $0.8$

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