Question

A projectile is moving at 60 m/s at its highest point, where it breaks into two equal parts due to an internal explosion. One part moves vertically up at 50 m/s with respect to ground, the part will move at speed of :

• A. $110m/s$
• B. $120m/s$
• C. $130m/s$
• D. $10\sqrt{61}m/s$

Answer 1

Answer: (D)

$10\sqrt{61}m/s$

Momentum conservation in y direction
$p,p_1$ and $p_2$ are momentum before collision and after collision
$p=0$ $p_{1y}=50$
momentum conservation in x direction
$p=60$ $p_{1y}=0$
$so{p}_{2y}=60$
$p_2=\sqrt{{50}^2+{60}^2}$
$p_2=10\sqrt{61}$