I Magnets, Outer space, and Rings

  • I
  • Thread starter Thread starter James William Hall
  • Start date Start date
  • Tags Tags
    Magnets Rings Space
AI Thread Summary
The discussion centers on whether a ring of iron filings could form around a magnet in space, with initial consensus suggesting that no ring would form, as most filings would either drift away or cling to the magnet. The possibility of a ring forming under different conditions, such as a spinning magnet or multiple magnets, is questioned. It is noted that for a stable ring system to develop, there must be a situation that allows for the circulation of particles, akin to orbital dynamics. The conversation references a previous thread on the topic, indicating ongoing interest in the physics of magnetic fields and particle behavior in space. Ultimately, the inquiry remains focused on identifying scenarios where a ring could indeed form around a magnet.
James William Hall
Gold Member
Messages
24
Reaction score
23
Awhile back there was a discussion about the following scenario: an astronaut sets free into space outside his window a round magnet so it just sits there a distance away ensuring the spaceship has no effect on the experiment. Then he wafts out gently a large pail of tiny iron filings and dust in the direction of the magnet and watches to see if a ring (ala Saturn) forms around the magnet at just the right distance from it. I believe the consensus was that no ring would form and that some filings would drift away and the rest cling to the magnet though there were dissenters. But I can’t remember if a different outcome, a ring, would form if the magnet was spinning or any other scenario where the ring would form. For instance if there were two magnet balls separated a short distance from one another or if they were bar magnets. So, the question is: is there any scenario where the ring would form?
 
Physics news on Phys.org
James William Hall said:
So, the question is: is there any scenario where the ring would form?
Any situation that supports circulation of particles, like in an orbit, must develop a ring system. That is the only topology that can avoid dynamic interactions and collisions, that is, once it has stabilised.
 
Berkeman, thank you for the thread.
 
Thread 'Gauss' law seems to imply instantaneous electric field propagation'
Imagine a charged sphere at the origin connected through an open switch to a vertical grounded wire. We wish to find an expression for the horizontal component of the electric field at a distance ##\mathbf{r}## from the sphere as it discharges. By using the Lorenz gauge condition: $$\nabla \cdot \mathbf{A} + \frac{1}{c^2}\frac{\partial \phi}{\partial t}=0\tag{1}$$ we find the following retarded solutions to the Maxwell equations If we assume that...
Thread 'Griffith, Electrodynamics, 4th Edition, Example 4.8. (First part)'
I am reading the Griffith, Electrodynamics book, 4th edition, Example 4.8 and stuck at some statements. It's little bit confused. > Example 4.8. Suppose the entire region below the plane ##z=0## in Fig. 4.28 is filled with uniform linear dielectric material of susceptibility ##\chi_e##. Calculate the force on a point charge ##q## situated a distance ##d## above the origin. Solution : The surface bound charge on the ##xy## plane is of opposite sign to ##q##, so the force will be...
Dear all, in an encounter of an infamous claim by Gerlich and Tscheuschner that the Greenhouse effect is inconsistent with the 2nd law of thermodynamics I came to a simple thought experiment which I wanted to share with you to check my understanding and brush up my knowledge. The thought experiment I tried to calculate through is as follows. I have a sphere (1) with radius ##r##, acting like a black body at a temperature of exactly ##T_1 = 500 K##. With Stefan-Boltzmann you can calculate...
Back
Top