In perfectly inelastic collisions, the relative velocity of the bodies

In perfectly inelastic collisions, the relative velocity of the bodies
  1. before impact is zero
  2. before impact is equal to that after impact
  3. after impact is zero
  4. is characterised by none of the above

Solution

We know that, in perfectly inelastic collisions between two bodies, both bodies move together with same velocity after impact.
$\therefore$ Relative velocity after impact, $\mathbf{v}_{\text {Rel }}=\mathbf{v}_1-\mathbf{v}_2=\mathbf{v}-\mathbf{v}=0$

Asked in: AP EAMCET 2021 (24 Aug Shift 2)

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