Question

Question #19991

Answer 1

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`