What Happens When an Object with Zero Rotational Inertia Spins?

AI Thread Summary
The discussion centers on the concept of an object with zero rotational inertia and the implications of such a scenario. Participants argue that an object cannot exist without inertia, as inertia is inherently linked to mass. The idea of a point mass lacking rotational inertia is debated, with emphasis on the challenges of defining the spinning of a dimensionless point. The conversation highlights the confusion surrounding hypothetical situations that contradict established physics principles. Ultimately, the concept of spinning without inertia is deemed not physically meaningful.
Mt. Nixion
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Let's say that something is spinning and it spins in a certian direction. The object has rotational inertia. Now say that the object has no inertia. How many times will the object change its direction of rotation in under a second?
 
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I am not understsnding yous question.whenever there is mass there is inertia.I think you can't think of object without inertia.
 
A point mass would have no rotational inertia. However, spinning of a point is not very well defined.
 
Mt. Nixion said:
Let's say that something is spinning and it spins in a certian direction. The object has rotational inertia. Now say that the object has no inertia. How many times will the object change its direction of rotation in under a second?
I don't understand the point of this (and most of the questions you've posted here). They usually start with a half-described situtation, then you ask what amounts to "what would happen if what we know about physics (or reality) wasn't true?". It's hard to tell if you are serious or just goofing around; if serious, what kind of answer are you expecting?

In this particular case, assuming the object has no inertia is not physically meaningful.
 
DavidK said:
A point mass would have no rotational inertia. However, spinning of a point is not very well defined.
How can the spinning of a point which has no dimension be defined.
 
vaishakh said:
How can the spinning of a point which has no dimension be defined.

It is not.

DavidK said:
However, spinning of a point is not very well defined.
 
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