Effects of a static magnet on a pulsed electromagnetic field?

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Discussion Overview

The discussion centers around the interaction between a static magnetic field and a pulsed electromagnetic field (PEMF). Participants explore whether a static magnet can influence a nearby pulsed field, particularly in terms of strength, direction, and frequency, while considering the implications of Maxwell's equations.

Discussion Character

  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions if a static magnetic field can influence a weaker pulsed electromagnetic field nearby, particularly if the static field is of equal or greater strength.
  • Another participant asserts that Maxwell's equations are linear, suggesting that the resulting field is simply the sum of the static and pulsed fields, leading to a clarification on the meaning of "influence."
  • A participant seeks clarification on the expected impact of a static magnet of approximately 40,000 microTesla on a PEMF of 50 microTesla, particularly at a distance of 1.5 cm from the coils generating the PEMF.
  • There is a discussion about the superposition principle, with one participant noting that the sum of the fields is only valid at a specific distance and that field strength varies with distance.
  • Further questions arise regarding the extent of the static magnet's field at 1 cm distance, whether the PEMF returns to its original strength after leaving the static field, and if there are changes in direction or frequency of the PEMF wave.
  • One participant suggests that a detailed description of the experimental setup would be beneficial for understanding the results.
  • Another participant emphasizes the complexity of non-mathematical descriptions of field behavior and recommends using software for field distribution calculations.

Areas of Agreement / Disagreement

Participants express differing views on the influence of static and pulsed fields, with some asserting the linearity of Maxwell's equations while others seek to understand the practical implications of these theoretical concepts. The discussion remains unresolved regarding the specific effects observed in the experimental context.

Contextual Notes

Participants note the importance of distance in determining field strength and the potential variability of magnetic fields, which may affect the interpretation of results. There is also mention of the need for a clear understanding of the experimental setup to draw more accurate conclusions.

Maggz
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Summary: Does a static magnetic field affect a weaker pulsed magnetic field close by?

If you have a static magnet close to a low level pulsed electromagnetic field, will the static magnetic field influence the pulsed field if the static magnetic field is the same strength or stronger than the pulsed field? If not, why not?
 
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Maxwell's equations are linear, so the resulting field will just be the sum of the static magnetic field and the pulsed field that would be present without the static field. So it depends what you mean by "influence", but there is no non-linear interaction, only a simple sum.
 
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Thank you very much for your answer. This is not my field, so my apologies for the simple questions. To be more specific, if you had a static magnet of approx. 40,000 microTesla situated approximately 1cm from coils generating PEMF of 50 microTesla, would you expect to see an impact on the 50 microTesla wave 1.5 cm away from the coils (in the opposite direction of the magnet.)? I guess the distance of the coils and the target site from the static magnet would make a difference? I am asking because in our testing we have seen no difference ( the delivered signal is the same as the emitted PEMF signal). It would be good to understand the mechanism behind this. As I understand your answer, according to Maxwell's equation, the measurement would be 40,050microTesla where the PEMF met the static field? (Would this return to 50microTesla as soon as the PEMF wave left the area of the static magnetism?).
 
Maggz said:
40,000 microTesla situated approximately 1cm from coils generating PEMF of 50 microTesla
Maggz said:
As I understand your answer, according to Maxwell's equation, the measurement would be 40,050microTesla where the PEMF met the static field?

Superposition is the correct physics. But your sum of 40050 is correct only if the strength of those two fields is 40000 and 50 at 1 cm distance. The strength of fields vary with distance.
 
Thank you. That is very helpful. So, I guess it would be helpful to know 1. 'Would a static magnet of 40,000microTesla be exerting any kind of field 1cm from its surface and 2. Does the PEMF wave revert back to its original strength of 50mT after leaving the static magnetic field? 3. (According to the first answer) Is it correct to say that there would be no change in direction or frequency of the PEMF wave? Really appreciate the help with this. We have observed the effects we want (PEMF measurements of 50mT at desired frequency 1.5 cm away from coils) in close proximity to static magnet (of 40,000mTesla approx 1 cm away). I am trying to find to find a 'textbook' answer to why this occurs so we can explain it easily to those with some basic knowledge of physics.
 
It would be useful if you could describe your setup. How you generate the pulse and how you detect the magnetic fields.
 
As @phyzguy already said, Maxwell's Equations describe how the fields behave in space. Non-mathematical descriptions are difficult and I do not recommend them.

You could use a software package like Ansys Maxwell to calculate the field distribution.
 

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