Diamagnetism confusion -- Does diamagnetism really have to do with Lenz’s law?

AI Thread Summary
Diamagnetism is a quantum phenomenon that is not related to Lenz's law, which applies to changing magnetic fields. All atoms exhibit diamagnetism even in steady magnetic fields, where the effect arises from electron orbits that exclude magnetic flux. Textbook explanations often misrepresent this by likening it to induced eddy currents at the atomic level, which do not accurately capture the quantum nature of diamagnetism. Diamagnetic materials are repelled by magnets, and understanding this basic behavior may suffice for those not yet familiar with quantum mechanics. Overall, a qualitative grasp of diamagnetism, along with other magnetic types, is recommended for foundational knowledge.
yymm
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Homework Statement
Does diamagnetism really got to do with Lenz’s law?
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In my textbook, and on many websites it says that when placed in a magnetic field and then due to Lenz’s law a magnetic dipole moment is created in atoms and so the material gets attracted to the magnet? But then in the case I bring the magnet close to the material very slowly( so the change in magnetic flux is very low), or I put the magnet there for a long time, stationary, then does that mean the material no longer gets magnetised?
 
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What kind of material? The diamagnetic materials are not attracted.
 
The answer is that Lenz's law has nothing to do with diamagnetism which is a quantum phenomenon. Lenz's law involves changing magnetic fields. However, all atoms exhibit diamagnetism and do so in steady magnetic fields. The effect has to do with electron orbits excluding magnetic flux. I think your textbook explanation is an attempt to explain diamagnetism as induced eddy currents at the atomic level. As is usual with classical models applied to quantum phenomena, the model falls short.

This Wikipedia article has more information.
 
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nasu said:
What kind of material? The diamagnetic materials are not attracted.
sorry I was meant to say repel instead of attract. Thanks for picking it up!
 
kuruman said:
The answer is that Lenz's law has nothing to do with diamagnetism which is a quantum phenomenon. Lenz's law involves changing magnetic fields. However, all atoms exhibit diamagnetism and do so in steady magnetic fields. The effect has to do with electron orbits excluding magnetic flux. I think your textbook explanation is an attempt to explain diamagnetism as induced eddy currents at the atomic level. As is usual with classical models applied to quantum phenomena, the model falls short.

This Wikipedia article has more information.
Yeah probably. If I haven't studied quantum mechanics yet then is it enough to know that diamagnetic materials gets repelled?
 
yymm said:
##\dots~## yet then is it enough to know that diamagnetic materials gets repelled?
Enough for what? If you have not studied quantum mechanics but you are worried what will be on the next test, it is probably "enough" to know qualitatively the distinguishing features of diamagnetism, paramagnetism and ferromagnetism.
 
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