B Centrifugal force spinning Basketball

AI Thread Summary
Centrifugal force on water droplets on a spinning basketball is influenced by the ball's stippled surface, which helps retain droplets during rotation at speeds of 33 RPM, 45 RPM, and 78 RPM. The surface roughness and attraction between the droplets and the ball are strong enough to counteract gravity. At the equator, centrifugal force may lift droplets off the surface, but they remain stable due to surface tension and adhesion until speeds exceed 78 RPM. The discussion suggests that understanding the experiment's purpose could clarify the findings. Overall, the interaction between centrifugal force and surface properties is crucial in this context.
nick200000
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Hi, Looking for Centrifugal force on water droplets on my spinning Basketball at 33 RPM, 45 RPM and 78 RPM
 
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Welcome to PF.

It appears the stippled surface of the ball holds the droplets in position, so they do not move during rotation. Maybe drops stick to the worn tip of the bump or to contamination of the surface between bumps. That surface roughness, and attraction, is clearly strong enough to counter gravity.

A droplet near the equator or the pole will not be expected to migrate across the surface when the ball is spun. Near the equator, the force would tend to lift the droplet off the surface. But the rate of rotation, required to break free, would need to be greater than 78 RPM before overcoming the surface tension and the bond with the ball material.

It might help if we knew what you were trying to disprove with the experiment.
 
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