The largest railway gun ever built was called Gustav and was used briefly in World War II. The gun, mount, and train car had a total mass of 1.22 106 kg. The gun fired a projectile that was 80.0 cm in diameter and weighed 7502 kg. In the firing illustrated in the figure, the gun has been elevated at è = 18.2° above the horizontal. If the railway gun was at rest before firing and moved to the right at a speed v = 4.27 m/s immediately after firing, what was the speed of the projectile as it left the barrel (muzzle velocity)?

Question

The largest railway gun ever built was called Gustav and was used briefly in World War II. The gun, mount, and train car had a total mass of 1.22  106 kg. The gun fired a projectile that was 80.0 cm in diameter and weighed 7502 kg. In the firing illustrated in the figure, the gun has been elevated at è = 18.2° above the horizontal. If the railway gun was at rest before firing and moved to the right at a speed v = 4.27 m/s immediately after firing, what was the speed of the projectile as it left the barrel (muzzle velocity)?

drwls · Answer

The horizontal component of total momentum remained zero. Use that fact, and the rail car recoil velocity, to compute the muzzle velocity.