Because a talented person can throw it so that its' spin is effected by the air and changes it direction.
.
The surface of the ball is not smooth. The pores of the leather and the sewing of the thread gives the ball a non-uniform aerodynamic surface.
By causing the ball to spin forward relative to the flight of travel, the ball will create a lower pressure zone above the ball and the ball will rise up at the expense of losing energy more quickly.
By causing the ball to spin in other directions relative to the path of flight the ball will fly accordingly.
The threading adds certain qualities to the aerodynamics that can be used by the pitcher to accentuate certain behaviors.
Fast ball, curve ball, drop ball, screw ball, rise ball, change up, curve drop, off speed curve.
Yes, the curve ball curves. This is because of the way the ball is thrown, which is a kind of a spin/jerky fast motion.
When a fast ball and curve ball are mixed together it is called a slider.
you curve the ball by shooting the ball n curve either right or left with the left or right arrow keyz
A fast ball is when the pitchers throws the ball straight at the strike zone, it doesn't curve (curve ball) or lower (slider), it goes straight ahead.
Three things affect the trajectory of a curve ball: Coriolis effect, gravity and precession AKA spin drift.
which fingers on a pitcher's throwing hand controls a curve ball and a slider
The straight ball.
Straght ball,hook ball, curve ball, backup ball.
Straght ball,hook ball, curve ball, backup ball.
curve
back up ball, hook ball, curve ball,