{{page>wiki:headers:hheader}}



=====The Magnetic Dipole Moment (10 minutes)=====
  * This lecture is best done by transitioning from the final answer of the [[..:..:activities:spact:splorentzforce|Lorentz Force and Work on a Rectangular Loop]] activity.  The term in the final answer contributed from the magnetic dipole moment can be singled out.  Then, the general expression

$$U=- \vec{\mu} \cdot \vec{B}$$

can be written on the board.

  * In words, the magnetic dipole moment is a measure of how much the current-carrying object's surface normal (which faces the same direction as the magnetic dipole moment vector) wants to face in the direction of the magnetic field.
  * Classically, it would be expected that, in the case of the Stern-Gerlach experiment, the silver atoms would all have "rings of charge" (their single shell electron) facing with their normals in random directions.  However, the results of the Stern-Gerlach experiment do not reflect this.


{{page>wiki:footers:courses:spfooter}}