Understanding the Effects of Rotation on Falling Objects

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Rotation does not inherently make falling objects move slower; rather, it can influence their motion when air friction is considered. In scenarios like helicopters, rotation can create lift by altering the pressure differential. The impact of rotation on falling objects is also dependent on their geometry. For example, a spiraling football may descend faster than a freely falling object due to air friction. The equations governing these dynamics are complex and involve fluid mechanics, as asymmetric rotational motion can generate various vortices that affect the object's fall.
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could someone explain how rotation makes falling objects move slower?
 
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It doesn't, unless you account for air friction, in which case there is a lift force that pushes up in some cases. You can think of it as changing the pressure differential that generates the lift, assuming we're talking about something like say a helicopter.

edit.. In the general case of a three dimensional object a lot will depend on the geometry of the object. For instance, it might actually speed up the object (relative to another that is free fall with air friction), think spiralling football plummeting to the earth.

The eqns are rather complicated, and an exercise in fluid mechanics for the general case.. Since lots of little vortices can be created by asymetric rotational motion.
 
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