Question

A projectile is moving at $20\,m\,s^{-1}$ at its highest point, where it breaks into two equal parts due to an internal explosion. One part moves vertically up at $30\,m\,s^{-1}$ with respect to the ground. Then the other part will move at

• A. $10\sqrt{13}m\,s^{-1}$
• B. $20\,m\,s^{-1}$
• C. $30\,m\,s^{-1}$
• D. $50\,m\,s^{-1}$

Answer 1

The Correct Option is D

Using momentum conservation,
$
\begin{array}{l}
m \times 20 \hat{ i }= m / 2 \times 30 \hat{ j }+ m / 2 \times x \\
x =40 \hat{ i }-30 \hat{ j } \\
\Rightarrow| x |=50
\end{array}
$