Xkcd (angular momentum problem)

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Spinning counterclockwise in the northern hemisphere does theoretically affect Earth's angular momentum, as it involves pushing against the planet. This action results in a minuscule decrease in Earth's rotational speed due to the conservation of momentum. When a person runs, they momentarily slow the Earth down, but stopping will reverse this effect, restoring its speed. The overall angular momentum of the Earth-person system remains conserved throughout the process. Thus, individual actions can have a measurable, albeit negligible, impact on Earth's rotation.
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I was reading xkcd and wondering if spinning in a counterclockwise way (on the northern hemisphere) would actually steal some of Earth's angular momentum and slow it down a bit. Is it possible or does this violate conservation of momentum?
 
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The angular momentum of the system = earth+you is conserved.
If you start running you do slow the Earth down as you push against it, then as you stop you speed it back up (or the other way around depending which direction you run in).
 

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