A machine gun is mounted on a 2000kg car on a harizontal frictionless surface. At some instant the gun fires bullets of mass 10gm 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

Options

A. 550 N
B. 50 N
C. 250 N
D. 250 N

Answer

B

Explanation

`u=` velocity of bullet
`(dm)/(dt)=` Mass thrown per second by the machine gun
`=`mass of bullet`xx`Number of bullet fired per second
`=10gxx10(bull et)/(sec)=100(g)/(sec)=0.1(kg)/(sec)`
Thrust`=(udm)/(dt)=500xx0.1=50N`