MCQ
Two particles $A$ and $B$ are projected simultaneously from a fixed point of the ground. Particle $A$ is projected on a smooth horizontal surface with speed $v$, while particle $B$ is projected in air with speed $\frac{2 v}{\sqrt{3}}$. If particle $B$ hits the particle $A$, the angle of projection of $B$ with the vertical is
  • A
    $30$
  • $60$
  • C
    $45$
  • D
    Both $(a)$ and $(b)$

Answer

Correct option: B.
$60$
b
(b)

Their horizontal components should be same.

$\therefore \quad \frac{2 v}{\sqrt{3}} \cdot \cos \theta=v$

or $\theta=60^{\circ}$

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