Question #19991

1 Answer
Oct 2, 2015

An impulse of #50Ns# is needed to keep the gun in position

Explanation:

The gun fires 600 bullets per minute, which is the same as 10 bullets per second. Each bullet has mass #25g#, which is equal to #0.025kg#. 10 bullets, each of mass #0.025kg# leaving the muzzle at #200 m//s# have a momentum, #mv# of:
#=>10xx0.025kgxx200m//s = 50 kg m//s#

The force required to change momentum is called impulse. It is the product of force and time, #Fxxt#, that is required to cause a change in momentum of #Deltamv#. It is derived as shown:
#F=mxxa#
#=> F=mxx(Deltav//t)#
#therefore Fxxt =mxxDeltav#

Here, your value of #mv# is #50kgm//s# and hence your value of #Fxxt# should be #50Ns#