It is interesting to see the demo for "Conservation of angular momentum". The MIT2K series has an excellent video on the conservation of angular momentum.
When he rotate the wheel, it has an angular momentum say $L$. The angular moment is given by $L=r\times \omega$ where $\omega$ is the angular frequency (which can be rewritten as $2\pi \nu$). This quantity is constant as for as no other forces acting on it. Now, when he flip the wheel, what happens? Isn't that really amazing? He starts to rotate. Why he starts to rotate? Because, when he rotate the wheel, the angular momentum directs downward (previously upward). Since angular momentum is conserved, it has to still $L$. So, the system make the demostrator to roate (with an angular momentum of $2L$ so that the total angular momentum is still $2L-L=L$. Gotcha...
Isn't that really amazing!!!
Questions:
How angular momentum conservation plays role in magnetism?
In a magnet, the angular momenta of all the electrons is alighted up. If we flip the magnet, does this has the same effect (i mean similar effect) as in the case of the rotating wheel here?
Is there any relation to the quantum hall effect, fractional quantum hall effect?
Questions:
How angular momentum conservation plays role in magnetism?
In a magnet, the angular momenta of all the electrons is alighted up. If we flip the magnet, does this has the same effect (i mean similar effect) as in the case of the rotating wheel here?
Is there any relation to the quantum hall effect, fractional quantum hall effect?
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