Anamolous Aerodynamic behaviour of small spheres?

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John_RB
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This refers to the behaviour of cricket balls. Every cricketer in the world believes that a cricket ball "swings" more when the atmospheric conditions are cool and damp (as in the UK) as opposed to hot and dry (as in Australia). I have watched a bit of baseball and I have never heard commentatators mention atmospheric conditions affecting the flight of the ball. Once the ball has left the hand there are only two forces acting - gravity and air resistance. "Swing" refers to the ball moving horizontally to the propelled direction (as well as vertically downwards of course).
 
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Cool air is denser and would have more noticeable aerodynamic effects. On the other hand, humid air is less dense, so that should decrease the aerodynamic effects. So I don't know why cool, humid air would be that different. (see figure in https://www.engineeringtoolbox.com/density-air-d_680.html )

CORRECTION: I see in the figure in the link, that humidity has little effect in the temperature range of a sports event. So the primary effect would be the increased density of cold air. That should increase any aerodynamic effects in cold temperatures.
 
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Does the baseball have a seam like a cricket ball? The seam is positioned at an angle to the path of the ball and makes the boundary layer unequal on the two sides, creating a sideways force.
 
tech99 said:
Does the baseball have a seam like a cricket ball? The seam is positioned at an angle to the path of the ball and makes the boundary layer unequal on the two sides, creating a sideways force.
Yes, the baseball has a seam and the pitcher often throws a ball that will maneuver different ways in flight: "curve ball", "knuckle ball", "slider", etc. But I don't remember hearing them comment on the effect of temperature or humidity on that aspect. They may have.