Can an electric field exist without a magnetic field, and can magnetic field exist without an electr

[m25]

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Can an electric field exist without a magnetic field, and can magnetic field exist without an electric field?

 

[Cawolf]

Electric fields can exist without a magnetic field - consider a stationary point charge.

Magnetic fields cannot exist without any E field component because there are no magnetic monopoles.

 

[sazerac]

Electric fields can exist without a magnetic field - consider a stationary point charge.

Magnetic fields cannot exist without any E field component because there are no magnetic monopoles.

Not happy with the second half of your answer.

A stationary electric charge creates an electric field.
A changing electric field creates a magnetic field.

Likewise, a stationary dipole magnet (e.g. a magnetized lump of iron) creates a magnetic field.
A changing magnetic field creates an electric field.

 

[Cawolf]

Not happy with the second half of your answer.

How so?

A stationary electric charge creates an electric field.
A changing electric field creates a magnetic field.

Agree.

A changing magnetic field creates an electric field.

Agree.

Likewise, a stationary dipole magnet (e.g. a magnetized lump of iron) creates a magnetic field.

I assume this is where you disagree? You are of course correct, we observe it all the time - every magnet we experience is not an electromagnet. I make the sweeping statement of no magnetic field without an electric field due to the nature of permanent magnet B field generation. It has been shown that the B field of permanent magnets is due to electron flow around the ferromagnetic nuclei with incomplete cancelling of net charge flow. It really is no different than a solenoid, except it is microscopic. Therefore there is a current (with an E field) generating the B field observable in a permanent magnet.

I believe that to be true and think it supports my prior statement.

Or maybe I just missed your point of contention.

 

[sazerac]

Oh, well if you're gonna get all technical on me ;-)

 

[Cawolf]

Just the way I learned it. 🙂

Since it aligns with Maxwell's statements, it is most likely the "expected" answer if questioned in first-year physics.

 

[m25]

Just the way I learned it. 🙂

Since it aligns with Maxwell's statements, it is most likely the "expected" answer if questioned in first-year physics.

Oh, well if you're gonna get all technical on me ;-)

What you guys are discussing is far beyond my understanding, but as far as the MCAT goes, is going with Cawolf's original answer okay?

 

[Cawolf]

I doubt you would see such a topic. Do you have a sample question that makes you think otherwise?

 

[m25]

I doubt you would see such a topic. Do you have a sample question that makes you think otherwise?

No I was just thinking I might need to know this for the MCAT, thanks!

 

[sazerac]

I never took calculus-based physics. I don't understand what in the hell cawolf is saying either, except maybe the part about how magnets secretly have spinning electrons. I've never met Maxwell.

I'm just going by what I was taught in algebra-based physics: changing E makes B, and changing B makes E. I imagine that is the right philosophy for the MCAT.

 

[Cawolf]

I don't think you will.

The basic concept of how changes in one effects the other is more than plenty, as @sazerac stated.

I've never met him either, and until Bill and Ted take me to the 19th century, I imagine we will just have to refer to his equations.