Read Paramagnets: Convert Magnetic Moment into Energy
A magnetic dipole has energy U = minus μ dot B. Parallel and antiparallel alignment differ by twice μ B.
Electricity questions depend on identifying charge, a conducting path and the condition that controls current or magnetic effect.
Magnetic effects have two poles and a direction
Like poles repel · unlike poles attract
Like poles repel and unlike poles attract. Keep the field direction and the material’s magnetic property separate.
Start with the condition
Build the governing relation
Room temperature explains why alignment is statistical, but the requested two-state energy gap comes directly from the dipole-field interaction.
Finish with a physical check
Check the limiting case before selecting an option: remove the special feature in the diagram or make the relevant parameter very large or very small. The result should reduce to a familiar relation.
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- ✓State the physical condition before choosing a formula.
- ✓Keep direction, sign and constraint information explicit.
- ✓Test one limiting case before committing to an option.
Using μ B instead of 2 μ B gives the energy of one orientation relative to zero, not the separation between the two orientations.
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