A machine gun fires 25g bullates at the rate of 600 per minute with a speed of 400 m/s . Calculate the force required to keep the gun in position. plz explain thanks in advance.

Dear Jayati

Force=rate of change of momentum= dP/dt=d(mv)/dt

F=v*dm/dt + m*dv/dt

here v is constant hence dv/dt=0

F=v*dm/dt

600 bullets are fired in 60sec

hence in one second 600/60=10 bullets

10 bullets=10x25=250 g= 0.25kg

dm/dt=0.25 kg/sec

F=400x0.25= 100N

hence 100N force is to be applied on gun to keep it in the position

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hi,

force required to keep the gun in position will be rate of change of momentum

600 bullets are fired in in 1minute the in one second 10 bullets are fired.

hence rate of change of momentum of bullets is 25*10*400/1000 newtons

by calculation we get,

force required=rate of change of momentum of bullet=100N

please approve if you like the answer

F = MvdN/dt

dN/dt = 600 per minute = 600 = 600/60 per second

         =10 per sec

F = 25*10^-3 *400*10

  =100N

thus 100N force is required

By the law of conservation of momentum20*V=600*. 025*400V=300 m/sUsing equationV=u+atU=0m/s. V=300m/s300=a*60. 1min=60seca=5m/s^2F=maF=20*5=100N