Air resistance on a rotating cylinder

AI Thread Summary
Air resistance on a rotating cylinder generates a drag torque that opposes its motion. This resistance is influenced by friction and viscosity, causing air to circulate around the cylinder, with velocity diminishing as distance from the surface increases. The drag force can be described using fluid dynamics principles, often involving parameters like the cylinder's speed, surface area, and air density. Understanding this interaction is crucial for predicting the cylinder's rotational behavior over time. Overall, air resistance plays a significant role in the dynamics of rotating objects in fluid environments.
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Hi, I have an object that's rotating in the air with constant speed. Now a bit simplified it could be looked as an uniform cylinder that's rotating round and round (not like a propeller). How would air resistance affect this rotation and how could you describe this force with a formula?

Thanks
 
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Friction and viscosity would cause the air to circulate in the vicinty of the cylinder, with the air's velocity decreasing with distance from the suface of the cylinder. The air's resitance to this would create an opposing drag torque on the cylinder.
 

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