MCQ
A vehicle travels half the distance with speed $v$ and the remaining distance with speed $2\,v$.Its average speed is :
  • A
    $\frac{3 v}{4}$
  • B
    $\frac{ v }{3}$
  • C
    $\frac{2 v}{3}$
  • $\frac{4 v}{3}$

Answer

Correct option: D.
$\frac{4 v}{3}$
d
$V_{a v g}=\frac{2 v_1 v_2}{v_1+v_2}=\frac{2(v)(2 v)}{v+2 v}=\frac{4 v^2}{3 v}=\frac{4 v}{3}$

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