I was holding a rubber band ball in my hand earlier and tossing it up in the air at about eye level. I noticed that I could see the shape of individual rubber bands on the axis of rotation on the outside of the ball but the edges of the ball were blurry. This got me thinking.. is a ball spinning slower near the axis than it is at the outer edge? Is the earth spinning faster at the equator than it is at the poles? If speed is d/t then the math makes sense to a layman like me that the ball would be rotating slower at the center and faster on the edges. Please help.
edit: holy shit. balls are fascinating.
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I consider this like a merry-go-round or a rotating circle. A point on the edge has a longer distance to travel to return to that same place than nearer the centre. The absolute centre on its axis does not have to travel anywhere. A rolling wheel travels further in one revolution the larger its circumference becomes.
A sphere is a 3D shape defined by a single distance from a point but still rotates around the same 1D axis with the same rules. A slice made through that sphere would produce a 2D circular intersection with the same properties as that circle from big, through smaller to a point at the poles where the axis intersects.
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