Originally Posted by 14ledo81
This can be confusing to some. The ball can't spin in two different directions at the same time. The ball will spin on one axis. The curvature will depend on how tilted the axis is.
I can move in one direction (say NNE) and still describe it as moving along two separate lines (north and east) simulaneously at a specific proportion....
Spin tilt can also be described as a vector sum of two orthogonal axis' (axes?, axises?).
For some, this is a great way to describe behavior by treating the horizontal effect and side spin effect separately to teach the physics of each component before discussing how they act combined to create a net flight.
AFAIK, the reason the ball tends to move later in the flight is because it has less velocity, so the tilted spin affects it more. Kind of like how a putt breaks more at the end than at the beginning. Somebody correct me if I'm wrong, please.
that's a good comment - spin effects happen due to the velocity of the ball (if the ball just sat in still air and spun, it wouldn't go anywhere (smart alecs are welcome to throw out coriolis effects now if they like) it has to be spinning and moving through the air).
I suspect the ball has a little roll as it flies and the final spin axis moves further toward side spin. this is a guess (ie., the spin axis migrates - since the initial momentum of the ball is forward, then the most drag in the early flight happens against the backspin "component" of spin on the ball)
someone here (likely Erik?) might even have access to the studies or measurements - I'm sure it's already been done.....
Edited by rehmwa - 6/23/14 at 2:50pm