Effects of a static magnet on a pulsed electromagnetic field?

[Maggz]

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?

 

[phyzguy]

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.

 

[Maggz]

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?).

 

[anorlunda]

40,000 microTesla situated approximately 1cm from coils generating PEMF of 50 microTesla

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.

 

[Maggz]

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.

 

[gleem]

It would be useful if you could describe your setup. How you generate the pulse and how you detect the magnetic fields.

 

[anorlunda]

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.