Rotating speed of a proton ion

[Javier Lopez]

I tried to calculted the rotating speed fro a proton from the clasical point of view by using its magnetic moment and the moment of a rotating sphere uniformly charged as example here: https://ocw.mit.edu/courses/physics/8-07-electromagnetism-ii-fall-2012/exams/MIT8_07F12_quizsol2.pdf
It is said that the magnetic moment is:
$$\overrightarrow{m}=\frac{1}{5}Qwr^2 \overrightarrow{z}=0.4*\pi Qfr^2\overrightarrow{z}$$
By using the electric charge radius of a proton: 8.8783E-16 (0.8783 fm), its charge: 1.602176565E-19 coulombs and magnetic moment 2.59008941428763E-23 J/T (all SI), then I obtained a rotating frequency of 1.632e26 hz and an equatorial surface speed of 9.1e11 m/s that is over the c speed limit

Note: the maximum magnetic moment is with an equatorial point charge which magnetic momentum is: $$\overrightarrow{m}=\pi Qfr^2 \overrightarrow{z}$$

There is also the calculus of the residual magnetic field flux density:

$$m=\frac{Br}{\mu }*Volume=\frac{Br}{\mu }*\frac{4}{3 }\pi *r^3$$

Then I obtained Br=1.11e16 teslas

Is there something wrong?

 

[Vanadium 50]

Is there something wrong?

clasical point of view

 

[PeroK]

Is there something wrong?

You need Quantum Mechanics for this.

 

[Javier Lopez]

May be interesting to explain 3000x times c :)
Relativistic theory could help also?

 

[Ibix]

May be interesting to explain 3000x times c :)
Relativistic theory could help also?

The problem is attempting to model a proton as a spinning ball. It isn't. Whether or not a spinning ball with a specified charge/radius/whatever is plausible isn't really relevant, except to hint that your model doesn't work.

 

[ZapperZ]

I tried to calculted the rotating speed fro a proton from the clasical point of view by using its magnetic moment and the moment of a rotating sphere uniformly charged as example here:Is there something wrong?

This is madness, and it shows that you missed the whole point of the existence of quantum mechanics.

I can understand if you're simply wanting to calculate the classically expected value of the magnetic moment, and that this is simply an exercise in curiosity. However, when you tried to compare it to the empirical results, and then scratched your head as to why they don't match or give absurd values, then you have completely missed the boat! This is why QM came into existence, because within this realm, classical mechanics does not work!.

Zz.

 

[Javier Lopez]

This is madness, and it shows that you missed the whole point of the existence of quantum mechanics.

I said not only is not consistent with classical physics but completely absurb because the error has some orders magnitude

QM is a group (large) of theories, the best theory is that explains better the result

We could try also relativity at short distances also:

$$Qe=\frac{Q}{\sqrt{1-\gamma^2}} $$

It could work at large distances (at large distance the charge is like static concentrated at centre of mass)

Unfortunately not fulfills Bremsstrahlung radiation, does the QM explain that?

Interesting question :)

 

[weirdoguy]

We could try also relativity at short distances also:

Or you could simply try to take seriously what others have told you several times: you can't use classical (non-relativistic nor relativistic) mechanics to calculate such things. Period.

 

[PeroK]

Unfortunately not fulfills Bremsstrahlung radiation, does the QM explain that?

QM explains everything.

Note that within QM you do not have Newton's laws. In particular, you cannot equate an attractive EM force and a centripetal force.

To give you an illustration: In the ground state of the hydrogen atom, a measurement of the angular momentum of the electron will always give the result 0. That means that in the ground state the "orbiting" electon has no angular momentum. In terms of classical mechanics this is absurd. But, QM works on potential and solutions to Schrodinger's equation; not to an equation balancing forces.

 

[Javier Lopez]

- I understand, but I wrote at the same time than following posts, so it seems that I did not read the posts -

In particular, you cannot equate an attractive EM force and a centripetal force.

Good point

It helped to me to know that the problem was not the equations but could be good that somebody gives a readable conclusion to the thread

The QM I learn was not useful to solve problems, I hope you had better luck

 

[mfb]

I said not only is not consistent with classical physics but completely absurb because the error has some orders magnitude

Yes, classical mechanics is completely unable to describe these things, it is not even a good approximation.

 

[Javier Lopez]

I have a magnetic simulator that works with high degree of accuracy off-axis, but uses useful equations and algorithms.
It would be wonderful to have something similar for close to nucleous.

It would work also equations obtained from tests, because I know a lot of tests were performed

What is the range where classic physics is out of range: one femtometer, ten femtometers?

I have done following plot that only have results from classical magnetic force and electrostatic force. I made it for 2 deuteriums but can be used for any nucleous:

I should write this and a lot more interestin formulas in my post about nuclear forces, but was not survived to QM battleships

 

[DrClaude]

Thread closed pending moderation.