When a quarterback is throwing a football, they will cock the football behind their head to begin the throw. This helps them throw the ball over the defense and farter to a teammate. Once the ball leaves the quarterback’s hand, it becomes a projectile and follows a parabolic path. As it travels in the air, the ball has to battle with gravity, which slows down the football. As the football reaches it max height, the ball lose all upward velocity, it stops for a very shot period of time. Then the ball start falling down, because gravity is acting upon the ball pulling the football down it starts to gain downward velocity. The path of the ball will form an arc. At the top of the arc, the ball reaches max hight and has a vertical velocity of 0 m/s, which means that the football's only motion at that point is horizontal.