Electromagnetism, flux density Vs. field size

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Discussion Overview

The discussion revolves around the relationship between electric current, magnetic flux density, and the size of the magnetic field in coils, particularly in the context of solenoids and the effects of introducing magnetic materials into the coils. Participants explore how increasing electric flow affects these properties and the implications of saturation in magnetic materials.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants propose that increasing electric current through a coil increases the magnetic flux density.
  • Others suggest that the magnetic field size is directly related to the magnetic flux, indicating that an increase in flux leads to an increase in the magnetic field.
  • A participant introduces the concept of saturation in magnetic materials, noting that the flux density is proportional to current up to a certain limit, beyond which the increase in field strength becomes less significant.
  • There is a question regarding the effect of electric current on the electric field within the wire, with some asserting that it also increases with current.
  • One participant mentions a natural tendency of systems to counterbalance disturbances from equilibrium, suggesting a broader conceptual framework for understanding these phenomena.
  • A later reply seeks clarification on frequency-weighting and the use of gauss meters, indicating a desire for more technical details related to measurement in this context.

Areas of Agreement / Disagreement

Participants generally agree that increasing electric current affects magnetic flux and field size, but there are competing views on the implications of saturation in magnetic materials and the relationship between electric and magnetic fields. The discussion remains unresolved regarding the specifics of these relationships and their broader implications.

Contextual Notes

Limitations include the need for proof regarding the monotonic relationship between electric current and magnetic flux, as well as the effects of saturation in different materials, which are not fully explored in the discussion.

semiotically
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With a set coil if you increase the electric flow does the flux density increase
And/or the magentic field decrease/ maintain/ increase in size..?

Thanks once again,

Sem.
 
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semiotically said:
With a set coil if you increase the electric flow does the flux density increase
And/or the magentic field decrease/ maintain/ increase in size..?

Thanks once again,

Sem.

You mean the magnetic flux through the middle of the coil (called a solenoid)? Yes, it increases if you increase the electric current through wire.

A lot of times the easiest way to see "what happens" is to take a process to a ridiculous proportion. For example, "what happens to magnetic flux if you decrease the electric field of a solenoid" can be answered by the question "what happens to the flux if you decrease the field all the way to 0, that is, turn off the electric field. Obviously the magnetic flux disappears. So yes, making your electric field get closer to 0 makes your magnetic flux get closer to 0 (this doesn't actually logically follow and a mathematician would want proof that the function relating the field to the flux is monotone increasing/decreasing and continuous for example but its good enough for some intuitive stuff).

So yeah, increasing the current increases the flux.
 
DukeofDuke said:
You mean the magnetic flux through the middle of the coil (called a solenoid)? Yes, it increases if you increase the electric current through wire.

A lot of times the easiest way to see "what happens" is to take a process to a ridiculous proportion. For example, "what happens to magnetic flux if you decrease the electric field of a solenoid" can be answered by the question "what happens to the flux if you decrease the field all the way to 0, that is, turn off the electric field. Obviously the magnetic flux disappears. So yes, making your electric field get closer to 0 makes your magnetic flux get closer to 0 (this doesn't actually logically follow and a mathematician would want proof that the function relating the field to the flux is monotone increasing/decreasing and continuous for example but its good enough for some intuitive stuff).

So yeah, increasing the current increases the flux.

And how does this affect the field size?
Thanks
 
which field, magnetic or electric?
The magnetic field goes up if the magnetic flux goes up...pretty much by definition
the electric field is present in the wire itself, and also goes up if the current goes up, again pretty trivially...
 
I think the ideia is related to a natural tendency that systems show to couterbalence disturbances from equilibrium
 
HI everyone,

I had a more definitive answer to the second half:

------------

Regarding Q2, when you have a coil without a soft magnetic material
(ferrite, steel, iron, etc) inside, the generated flux density B (or
magnetizing field H) is proportional to the current through the coil's
winding.

For coils with magnetic material, the core material can support a
limited flux density only (300...500 mT for ferrite, and 1.5..2T for
iron/steel). Up to the saturation point, the flux density is more or
less proportional to current to the winding. Above the saturation
level, the field does increase very slowly with increasing current.

---------------

Though I still need any help on frequency-weighting and 'flat' gauss meters..?
 

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