What is Ballistics?
'''Ballistics''' the study of the motion of [[projectile]]s (flying objects), mainly about [[bullet]]s which are fired from [[guns]] or [[cannon]], but also about the motion of spacecrafts, motion of balls in ball games, etc. The motion of projectiles can be expressed by [[Trajectory|trajectories]], which are the paths which a projectile takes. This science shows us the [[wikt:path|path]] and behavior of projectiles. Gun ballistics may be divided into the following four categories.<ref>{{cite book |url= http://www.fas.org/man/dod-101/sys/land/docs/fm6-40-ch3.htm |title=FM 6-40 Tactics, Techniques, and Procedures for Field Artillery Manual Cannonry |author=U.S. Marine Corps |publisher=Department of the Army |year=1996}}</ref> [[File:Newton Cannon.svg|thumb|Newton's gun cannonball [[projectile]]s.]] * ''Internal ballistics'' is about the motion of projectile inside [[Barrel (weapons)|barrel]] (tube part of gun). This motion depends on the pressure of gas, which is created by burning gunpowder. The pressure is depends on (is related to) the amount of [[gunpowder]] in the bullet, the type of gunpowder, size of pieces of gunpowder, free space behind a bullet and outside temperature. This motion also depends on the size and weight of bullet. The most important number from internal ballistics for performance is the [[muzzle velocity]] (projectile speed from the front edge of barrel). * ''Transition ballistics'' is the study about the behavior and changes in a nearby distance from the barrel. It studies the effect of gases going from a barrel behind a bullet, which are faster than bullet. These gases can affect the ballistic path, usually in a bad way. * ''External ballistics'' studies the trajectory of a projectile when it is outside of the object which accelerates it (such as when a bullet leaves the barrel of the gun, from which it is fired). This trajectory depends on three ballistic conditions - the beginning speed, the angle at which the object is thrown, and the ballistic [[Physical coefficient|coefficient]] (a