A person with machine gun can fire $50 \mathrm{~g}$ bullets with a velocity of $240 \mathrm{~m} /…
A person with machine gun can fire $50 \mathrm{~g}$ bullets with a velocity of $240 \mathrm{~m} / \mathrm{s}$. A $60 \mathrm{~kg}$ tiger moves towards him with a velocity of $12 \mathrm{~m} / \mathrm{s}$. In order to stop the tiger in track, the number of bullets the person fires towards the tiger is
$50$
$60$
$70$
$80$
Solution
In order to stop the tiger, the momentum of the bullets fired must be equal to the momentum of the tiger.
$\begin{array}{ll}
\therefore & \mathrm{MV}=\mathrm{nmv} \\
\therefore & \mathrm{n}=\frac{\mathrm{MV}}{\mathrm{mV}}=\frac{60 \times 12}{50 \times 10^{-3} \times 240} \\
\therefore & \mathrm{n}=60
\end{array}$