Why does a soccer ball bend without spin?

  • Context: High School 
  • Thread starter Thread starter Quadruple Bypass
  • Start date Start date
  • Tags Tags
    Ball Bend
Click For Summary

Discussion Overview

The discussion revolves around the phenomenon of a soccer ball bending in mid-air even when it is kicked with little to no spin. Participants explore various factors that might contribute to this behavior, including air flow, ball deformation, and surface texture, while referencing related concepts like the knuckleball in baseball.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant notes that a soccer ball can bend without spin, prompting curiosity about the underlying reasons.
  • Another participant questions whether the ball might still have some spin, suggesting that video illusions could misrepresent the ball's motion.
  • It is proposed that turbulent air flow could cause the ball to swerve, similar to a knuckleball in baseball.
  • A participant suggests that the ridges on the ball's surface and the deformation of the ball could contribute to its bending behavior.
  • One participant expresses uncertainty about consistently kicking the ball without spin and whether it bends in the same direction each time.
  • Another participant mentions that the erratic path of a knuckleball is influenced by the stitching on the ball, implying a similar effect may occur with the soccer ball.

Areas of Agreement / Disagreement

Participants express differing views on whether the bending occurs without spin and the factors contributing to it. There is no consensus on the exact reasons for the observed behavior of the soccer ball.

Contextual Notes

Some participants acknowledge the limitations of their observations, such as the potential for video distortion and the difficulty in consistently kicking the ball without spin.

Quadruple Bypass
Messages
120
Reaction score
0
yes i know the basics of how it curves (bends) in mid air, BUT, why does it bend when there is little to relatively no spin on it? i have noticed this a few times.PS: if you want to catch the craziest bend, here it is... [MEDIA=youtube]-_4WRdLniPY[/MEDIA]&search=roberto%20carlos[/URL]

EDIT: sorry i picked the wrong camera angle link, here is the other camera angle

[PLAIN][MEDIA=youtube]C83X7UBqXAE[/MEDIA]&search=roberto%20carlos[/URL]
 
Last edited by a moderator:
Physics news on Phys.org
My god that is impressive.
 
Are sure it doesn't have spin on it? Often videos can create the illusion that a spinning object is not spinning.

A good wind could also cause the ball to swerve.
 
Turbulent air flow. A "knuckleball" in hardball will move around a bit randomly, with little spin on it. I can't see the video though, I'm using IE, and apparently java-script isn't working (although I can see some other videos on you tube).
 
ah no no no, sorry. the video has nothing to do with the question, its just showing what a spinning ball CAN do. sometimes i kick a ball and it has absolutely no spin on it, but it still bends. could it have something to do with the warping of ball? the air inside bouncing from side to side? yea I am really going out on a limb here.
 
Honestly, I can't say for sure.If it truly is not spinning, it would have to be a combination of the unstable flow around the ball coupled with the ridges in the ball's skin. I think you may also have something in the idea of the deformation of the ball too.

The video linked looked like the ball did have spin on it though. However your experience tells you otherwise.

Let me ask you this...can you kick the ball consistantly with no spin? If so, does the ball bend the same way every time?
 
it could have something to do with the ridges and the air flow. and the times i kick it with no spin are the times when i am TRYING to put a spin on it (weird huh?). but its 50/50, so I am not consistent.
 
I'd be interested to see if it broke in the same direction consistantly with no spin. After doing a bit of looking around, I saw some good info on the knucklball pitch. It's path tends to be erratic which makes it hard to hit for the batter and hard to catch for the catcher. That erratic path is definitely due to the stitching on the ball. The same phenomenon must be happening here.
 

Similar threads

  • · Replies 7 ·
Replies
7
Views
2K
Replies
5
Views
5K
  • · Replies 6 ·
Replies
6
Views
7K
  • · Replies 39 ·
2
Replies
39
Views
2K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 1 ·
Replies
1
Views
4K
  • · Replies 2 ·
Replies
2
Views
3K
Replies
11
Views
3K
  • · Replies 11 ·
Replies
11
Views
8K
  • · Replies 69 ·
3
Replies
69
Views
17K