Does more angular monentum mean faster spin?

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SUMMARY

The discussion clarifies that having a higher angular momentum does not necessarily indicate a faster spin. Specifically, the angular momentum of an object is determined by the product of its moment of inertia and angular velocity. In the example provided, the Earth has an angular momentum of 100 units compared to a top's 12 units, but this does not imply that the Earth spins faster due to differing moments of inertia. The conclusion can only be drawn if both objects have the same mass and mass distribution.

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If a top has angular momentum of 12 units and the Earth has angular momentum of 100. Does this mean that Earth is spinning faster than the top since it has more angular momentum? The answer is there at the back of my head but can't articulate it.
 
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No. Angular velocity tells you what spins faster.
 
No. Angular momentum ( its magnitude) is the product of moment of inertia and the angular velocity. In your case the rotational inertia of the Earth and the top aren't equal, so you can't make the conclusion as you did.
 
Last edited:
Aniruddha@94 said:
No. Angular velocity ( its magnitude) is the product of moment of inertia and the angular velocity. In your case the rotational inertia of the Earth and the top aren't equal, so you can't make the conclusion as you did.

A typo, there, it's Angular Momentum that you meant.
 
sophiecentaur said:
A typo, there, it's Angular Momentum that you meant.
Aah yes, sorry.. I'll edit it. Thanks.
 
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As everyone else has said, the answer is no. You could only draw the conclusion you draw if the objects are the same (same mass and distribution of mass). To be more precise, the moment of inertia needs to be the same. I think you could draw this conclusion from other posts, but I just wanted to be explicit.
 

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