A machine gun fires a bullet of mass 40 g with a velocity `1200 ms^-1`. The man holding it can exert a maximum force of 144 N on the gun. How many bullets can be fire per second at the most? a) 3 b) 5 c) 6 d) 9

Options

A. One
B. Four
C. Two
D. Three

Answer

D

Explanation

`u=`velocity of bullet
`(dm)/(dt)=`mass fired per second by the gun
`(dm)/(dt)=`Mass of bullet`(m_B)xx`Bullets fired per sec (N)
Maximum force that man can exert `F=u((dm)/(dt))`
`impliesN=(F)/(m_bxxu)=(144)/(30xx10^3xx1200)=3`