Question

A machine gun is mounted on a $2000kg$ car on a horizontal frictionless surface. At some instant the gun fires bullets of mass $10g$ with a velocity of $500m/sec$ with respect to the car. The number of bullets fired per second is ten. The average thrust on the system is:

• A. $550newton$
• B. $50newton$
• C. $250newton$
• D. $250dyne$

Answer 1

Answer: (B)

$50newton$

$F=mnV$ where n is the no of bullets fired per sec
$\therefore F=(10\times {10}^{-3})\times 10\times 500=50N$