Projectile calculation notes

http://en.wikipedia.org/wiki/External_ballistics

http://en.wikipedia.org/wiki/Force#Newton.27s_second_law

http://www.projectshum.org/Gravity/newton.html

http://gafferongames.wordpress.com/game-physics/

http://en.wikipedia.org/wiki/Trajectory

http://en.wikipedia.org/wiki/Trajectory_of_a_projectile

comp.games.development.programming.algorithms...

http://formularium.org/en/10.html?go=88.114

http://en.wikibooks.org/wiki/High_school_physics/Projectile_motion

http://forums.xna.com/forums/p/4832/40259.aspx#40259