Question

give me the solution plz

Answer 1

Let mass of machine gun be M kg
Let mass of each bullet be m kg
Total bullets fired = 400
Apllying the conseravation of momentun
MV=mv
20000×V=400×35×400
V=280m/s
Let acceleration of gun in opposite direction be a
a=V/t=280/60=4.67m/s^2
F=M×a=20×4.67=93.4N
Hence, the answer is (a)