Why do knuckleballs move

Usually, a knuckleball rotates one to three times on its way to the batter, and the ball usually spins about an approximately vertical axis — that is, with side spin.

Sometimes, the ball spins about a different axis, depending on which fingers push the hardest. To demonstrate that it is not all that difficult to pitch a knuckleball, this QuickTime video shows an example where I threw a knuckball and filmed it at fps.

The hard part is to throw it accurately, relatively fast and consistently well. I cheated by throwing a very light polystyrene ball with string glued to the ball to simulate a raised seam. However, the physics of the problem is exactly the same, regardless of the mass or diameter of the ball, and that is what I was interested in.

Rather, the ball curved first in one direction and then in the opposite direction. It depends on how the seam is aligned and how the spin axis is aligned and how fast the ball is spinning.

This video shows that some of my knuckleballs curved in only one direction. The ball curved 24 cm sideways after traveling a distance of 6 m to the length of string stretched across the front of the camera. In this case, the curve can be explained by the smooth patch on the left side of the ball, which is equivalent to having an illegal rough patch on the opposite side.

As the ball rotates, no part of the seam enters the smooth patch. The seam is highlighted by a dashed line drawn along the seam ie string. Can YOU hit a knuckleball? This first movie shows a knuckleball headed your way. These fluctuations cause the ball to move in such a seemingly unnatural way. The knuckleball, however, is not exclusive to just a soccer ball or a baseball. To this day, the knuckleball leaves opposing batters and goalkeepers bamboozled and frozen by the unpredictable, erratic ways that the ball moves towards them.

Though extremely difficult to master, many goal-scorers and pitchers will continue to use the knuckleball to their advantage in the coming years. The knuckleball is such a valuable pitch in baseball. It takes a lot of time to perfect a knuckleball as well as a tremendous amount of hard work and effort. An interesting point you made is how the knuckleball is not only in baseball and soccer but also almost any ball can knuckle.

I play goalie in soccer and have experienced so many times a ball that knuckles, which obviously is so hard to save. Knuckleballs are my worst nightmare, but observing them move are fascinating. I thought that this was a very interesting idea for a blog post.

I also watched as he struggled at times to perfect the very difficult technique required to throw the pitch. I did further research into the knuckleball, and found that normal fastballs rely on a gyroscopic effect from spin that gives them a straight trajectory. This makes it increasingly difficult to trace where seafood goes and difficult to The tone of Twitter posts can predict when a team is more likely to win and ScienceDaily shares links with sites in the TrendMD network and earns revenue from third-party advertisers, where indicated.

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