Question

A machine gun fires 50gm bullets at a speed of 1000m/s. The gunner, holding the machine gun in his hands, can exert an average force of 180N against the gun. Determine the maximum number of bullets he can fire per minute

Answer 1

The impulsive force

$I=mv \\ I= 50 \times 10^{-3} \times 1000 = 50$

If man can hold the gun at a recoiling force of 180 N in 1 min

t= 60 s

F= 180 N

Number of bullets per min $= \frac{Ft}{I}$

$= \frac{180 \times 60}{50}=216$

Answer: 216