Will Changing an Inductor's Core Affect Voltage Drop with Constant DC Current?

[ed stars]

Suppose you have a pure DC supply with a constant current to an inductor. And you change the core of the inductor from air to iron, leaving the current remain the same. You may try changing to other materials. Does the voltage drop across the inductor will remain the same for any core? Anyone who performed an experiment on this? Or have an answer. Note, I am not referring to changing magnetic field. Voltage measurement should be done during the time the magnetic field becomes stable.

 

[tech99]

Suppose you have a pure DC supply with a constant current to an inductor. And you change the core of the inductor from air to iron, leaving the current remain the same. You may try changing to other materials. Does the voltage drop across the inductor will remain the same for any core? Anyone who performed an experiment on this? Or have an answer. Note, I am not referring to changing magnetic field. Voltage measurement should be done during the time the magnetic field becomes stable.

The DC resistance is unaltered when you change the core, so the voltage will be the same.

 

[ed stars]

To tech99. The DC resistance you might be referring is due to the winding of the wire, which will always be constant regardless of the core. This is the basis of voltage drop. I am curious if the core has effect on voltage drop in addition to the wire windings.

 

[ed stars]

I found this post in one of the forum. I am not sure if this an experimental proof. "Why does the resistance of an inductor increase when an iron core is introduced?"

 

[jim hardy]

I found this post in one of the forum.

That thread
https://www.physicsforums.com/threa...rease-when-an-iron-core-is-introduced.590639/

answers the question several times from different approaches.

OP should read the thread to its end.

 

[tech99]

I found this post in one of the forum. I am not sure if this an experimental proof. "Why does the resistance of an inductor increase when an iron core is introduced?"

The resistance for AC will increase when a core is introduced due to increased skin effect. But for static conditions, as asked in the question, the DC resistance of the winding does not alter when a core is introduced.

 

[ed stars]

The resistance for AC will increase when a core is introduced due to increased skin effect. But for static conditions, as asked in the question, the DC resistance of the winding does not alter when a core is introduced.

thanks tech99. i am thinking what will happen if we put a diamagnetic material in the core. will it affect the voltage drop due to the counter emf?