MCQ
Two particles $P$ and $Q$ simultaneously start moving from point $A$ with velocities $15\,m / s$ and $20\,m / s$ respectively. The two particles move with accelerations equal in magnitude but opposite in direction. When $P$ overtakes $Q$ at $B$, then its velocity is $30\,m / s$. The velocity of $Q$ at point $B$ will be $..........\,m/s$
  • A
    $30$
  • $5$
  • C
    $20$
  • D
    $15$

Answer

Correct option: B.
$5$
b
(b)

For $P, 30=15+a t$

or $\quad a t=15\,m / s$

For $Q, v=20- at$

$v=20-15=5\,m / s$

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