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.
In: 439
Yes and no.
From a scalar speed perspective (distance / time), the answer is no. As you surmised, close to the poles (axis of rotation) the amount of distance covered in one revolution is less than at the equator. Therefore the tangential speed is higher farther away from the poles.
But from an angular (rotational) speed perspective, the answer is yes. Each part of the sphere completes one rotation (360⁰ or 2π radians) within the same time, so that will be constant throughout the whole sphere.
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