Why doesn't a spinning coin flip over?

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A spinning coin remains upright due to the conservation of angular momentum, similar to a spinning top. The forces acting on the coin create a stable gyroscopic effect, preventing it from falling flat. The discussion references Euler's equations to explain the dynamics involved, noting that the coin's rotational inertia around its axis contributes to its stability. The oscillation of angular velocities in different axes further supports this behavior. Understanding these principles clarifies why a spinning coin does not simply flop over onto its side.
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I would be satisfied with a qualitative explanation(pure physical), but it would be nice if someone can also provide the mathematical model.



thanks
 
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Are you asking why it doesn't stop spinning and flop over onto one of its sides? Just not sure what you mean by "flip over".
 
Remember conservation of angular momentum.

ehild
 
Drakkith said:
Are you asking why it doesn't stop spinning and flop over onto one of its sides? Just not sure what you mean by "flip over".



oh sorry I should be more clear.

I meant why doesn't it fall down on the ground(flat) as a stationary coin would.
 
It follows from Euler's equations. If there is an Omega_z (z is the axis of the coin), and I_z is larger than I_x and I_y, Omega_x and Omega_y follow SHO, and oscillate without flipping over.
You can win money with that, just don't get caught.
 
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