MCQ
A projectile is projected at $30^{\circ}$ from horizontal with initial velocity $40\,ms ^{-1}$. The velocity of the projectile at $t =2\,s$ from the start will be $........$ (Given $g =10\,m / s ^2$ )
  • $20 \sqrt{3}\,ms ^{-1}$
  • B
    $40 \sqrt{3}\,ms ^{-1}$
  • C
    $20\,ms ^{-1}$
  • D
    Zero

Answer

Correct option: A.
$20 \sqrt{3}\,ms ^{-1}$
a
At $t =2$ particle is at maximum height moving with velocity $V =40 \cos 30^{\circ}=20 \sqrt{3}\,ms ^{-1}$.

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