Re: will a smooth surface ball curve when thrown??

A perfectly smooth ball cannot be made to curve. The stitches on a baseball 
disrupt the airflow around the ball, creating forces which move the ball 
out of a linear path. Golf balls do not hook or slice because of their 
surface, but rather because of the angle at which they are struck by the 
club. That is why the golfer's swinging technique is so important. What the 
dimples on a golf ball do is create small pockets of air around the ball, 
decreasing drag by improving what is known as "laminar flow", essentially 
greasing the ball's path through the air.