What is Reluctance in a Magnetic Circuit?

[Drew Drowden]

Electrical resistance is due to electrons colliding with the atoms of the conductor. In a magnetic circuit reluctance is analogous to resistance in an electric circuit. Just as resistance impedes the flow of electrons in an electric circuit, reluctance impedes the flux in a magnetic circuit but how does it do this? Since flux is the magnetic field lines per unit area how does the material increase or lower the number of field lines.

 

[CWatters]

It is easier to magnetize (create a magnetic flux in) some materials than others. As Wikipedia says.. "Air and vacuum have high reluctance, while easily magnetized materials such as soft iron have low reluctance".