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Some sources I've found state that refrigerator doors are built with permanent magnets:

Most refrigerators have sheet steel doors and the magnetic field lines pass through the door metal from the north poles of the sheet magnet to the south poles, making the magnet stick to the refrigerator door. https://van.physics.illinois.edu/qa/listing.php?id=363

One of the most common magnetic household items is the refrigerator door, however, the door is not the only part that is made from a permanent magnet. The gasket that seals the door closed also has a thin inner magnetic strip. www.sciencing.com/uses-permanent-magnets-5565745.html

But other sites say that magnetic fields are induced in refrigerator doors by the presence of nearby magnets:

How does a magnet attract screws, paper clips, refrigerators, etc? The materials are all "soft" ferromagnets. The external field temporarily aligns the domains so there is a net dipole, which is then attracted to the bar magnet. The effect vanishes with no applied B field. www.slideshare.net/erletshaqe1/lecture-23-magnetic-field-and-current (see slide 14)

The door is a magnetic material. The door will not retain its magnetism. www.northernhighlands.org/cms/lib5/NJ01000179/Centricity/domain/214/cp_physics/unit_9/key/p1.pdf

My question is: what do the magnetic field lines look like around a refrigerator door?

I'm primarily interested in refrigerator doors made with permanent magnets. (But if it turns out that no such refrigerator doors actually exist, then I'm interested in what the door's induced magnetic field lines look like when a magnet is placed near the refrigerator door.)

I don't have a compass handy to test it myself, and I haven't been able to find any diagrams online. My understanding is that it would be inappropriate to test the door's field using a normal refrigerator magnet because a refrigerator magnet has north and south poles facing the refrigerator: enter image description here

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  • $\begingroup$ Perhaps Wikipedia about Halbach array is what you are searching. $\endgroup$ – HolgerFiedler Apr 22 '17 at 21:17
  • $\begingroup$ Thanks for the reply! The image I included in my post is a Halbach array, and I know this design appears inside the magnets that we stick to the refrigerator door. Do Halbach arrays additionally appear in the refrigerator door itself? For example, if a refrigerator door is made with sheet steel, then is this sheet steel designed with a Halbach array? $\endgroup$ – jdphysics Apr 23 '17 at 2:18
  • $\begingroup$ Of course not as long as one use materials which could be magnetized and this is the case engineers are designing the opposite part of the fridge. $\endgroup$ – HolgerFiedler Apr 23 '17 at 4:58
  • $\begingroup$ When you say "use materials which could be magnetized" are you referring to the refrigerator door? In other words, are you suggesting that a refrigerator door is not made from permanent magnets, but rather, the door's field is induced by the Halbach array? And if this is the case, then are you suggesting that the induced field mirrors a Halbach array? Or do you mean something else by the "opposite" part of the fridge? $\endgroup$ – jdphysics Apr 23 '17 at 23:05

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