Consider a gravity free container as shown. System is initially at rest and electric potential in the regon is $V = (y^3+2)\  J/C$. A ball of charge $q$ and mass $m$ is released from rest from base starts to move up due to electric field and collides with the shaded face as shown.If its speed just after collision is $1.5\  m/s$ and time for which ball is in contact with shaded face is $0.1\ sec$, find external force required to hold the container fixed in its position during collision assuming ball exerts constant force on wall during entire span of collision.......$N$

822-378

  • A

    $70$

  • B

    $72$

  • C

    $74$

  • D

    $76$

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