Final answer:
The question pertains to the physics of firearms, specifically recoil and rifling. Recoil is the backward motion experienced when a gun is fired due to Newton's third law of motion. Rifling refers to the spiral grooves in a gun barrel that stabilize the projectile for greater accuracy.
Step-by-step explanation:
The subject at hand deals with the physics behind firearms including concepts such as recoil, rifling, and ballistics. When a bullet is fired from a rifle, the gun recoils or kicks backward due to Newton's third law of motion, which states that for every action there is an equal and opposite reaction. In the case of a military rifle, mechanisms such as a recoiling plunger absorb some of the recoil force. The plunger moves over a large distance and is stopped by damping mechanisms, which reduces the average force exerted on the shooter.
The calculation of the recoil velocity of the plunger and the subsequent force exerted upon it can be done using the principles of conservation of momentum and work-energy theorem. Assuming the bullet interacts directly with a 1.00-kg plunger and is fired at 600 m/s, the recoil velocity can be calculated. Then, the average force exerted on this part is found by considering the stopping distance, which in this scenario is 20.0 cm. Comparing this force to that exerted on a gun during the bullet's acceleration over a 10.0 ms period illustrates the benefits of such a recoil-reducing mechanism.
With regard to rifling, it's a design feature in the barrel of firearms, including cannons and rifles, which imparts a spin to the projectile. This spin stabilizes the projectile, increasing its accuracy and range. Rifling involves cutting spiral grooves into the interior of the gun barrel, and the raised areas between the grooves are known as lands.