Q. A machine gun mounted on a 2000 kg car on a horizontal frictionless surface fires 10 bullets per second. If 10 g be the mass of each bullet and 500 $ms^{- 1}$, the velocity of each bullet, then the acceleration of the car will be
A) $\frac{1}{10}ms^{- 2}$
B) $\frac{1}{20}ms^{- 2}$
C) $\frac{1}{40}ms^{- 2}$
D) $\frac{1}{60}ms^{- 2}$
Explanation
(c) Acceleration of the car $= \frac{Force\ on\ the\ car}{\begin{array}{r}
Mass\ of\ the\ car \\
\
\end{array}}$
$= \frac{mnv}{M} = \frac{0.01 \times 10 \times 500}{2000}ms^{- 2} = \frac{5}{200}ms^{- 2} = \frac{1}{40}ms^{- 2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.