Laws of Motion

A uniform meter scale of mass is suspended by two vertical strings attached to its two ends. a body of mass 2m is placed on 75 cm mark. the tension in the two strings are in the ratio
A machine gun of mass $$10\ kg$$ fires $$30\ g$$ bullets at the rate of $$6$$ bullet/s with a speed of $$400\ m/s$$. The force required to keep the gun in position will be