Documents about Magnetic Dipole Moment

  • 18 Pages

    Phys 0175 - Lecture 32

    Pittsburgh, PHYS 0175

    Excerpt: ... or spin) S. Associated with this spin is an intrinsic spin magnetic dipole moment S. For an electron the magnitude of S is B = eh/(4me) = 9.27x10-24 J/T which is called a Bohr magneton. In an external magnetic field Bext an electron rr B has potential energy U S g ext When an electron is bound to an atom, it has an additional angular momentum called orbital angular momentum Lorb because of its orbital motion. Associated with Lorb the electron has an orbital er r magnetic dipole moment orb Lorb 2me Both Lorb and orb are quantized, i.e. they can have only certain discrete values. When an atom is placed in an external magnetic field Bext, a potential energy U can be associated with the orientation of the orbital magnetic dipole moment of each electron in the atom. Its value is rr U orb g ext B Magnetic Materials: As we have just seen, each electron in an atom has a spin magnetic dipole moment and an orbital magnetic dipole moment which combine vectorially. The ve ...

  • 10 Pages


    University of Florida, PHY 2049

    Excerpt: ... PHY2061 Enriched Physics 2 Lecture Notes Magnetic Dipoles Magnetic Dipoles Disclaimer: These lecture notes are not meant to replace the course textbook. The content may be incomplete. Some topics may be unclear. These notes are only meant to be a study aid and a supplement to your own notes. Please report any inaccuracies to the professor. Magnetic Field of Current Loop B z R r x I y For distances R r (the loop radius), the calculation of the magnetic field does not depend on the shape of the current loop. It only depends on the current and the area (as well as R and ): 0 cos Br = 2 4 R 3 B= B = 0 sin 4 R 3 where = iA is the magnetic dipole moment of the loop Here i is the current in the loop, A is the loop area, R is the radial distance from the center of the loop, and is the polar angle from the Z-axis. The field is equivalent to that from a tiny bar magnet (a magnetic dipole). We define the magnetic dipole moment to be a vector pointin ...

  • 1 Pages


    Rhode Island, PHYS 204

    Excerpt: ... Magnetic Dipole in Uniform Magnetic Field Magnetic dipole moment : = IA^ n Torque exerted by magnetic field: = B Potential energy: U = - B Z Z ()d = B U () = - /2 sin d = -B cos /2 Note: () and d have opposite sign. . ^ = IAn ^ n I B tsl198 p.1/1 ...

  • 1 Pages


    UCLA, CHEM 113A

    Excerpt: ... Preview #14 (Chem113A W09, due Fri. 2/6/09 at 12:05pm in class) Attendance record: I am [ ] present at or [ Assigned reading: Engel 6.1-6.2 ] absent from this class meeting (see date and time above). Name:_ Forming study groups is permissible, but you must construct your solutions independently. By writing down my name, I confirm that I strictly obey the academic ethic code when doing this preview and my statement on attendance (above) is correct. Please write down the names of everyone who you worked with on this preview in the space above. [1] Commutator. Please change the momentum to the position x. [2] Stern-Gerlach experiments. This is the Stern-Gerlach experiment corresponding exactly to Fig. 6.3 (p. 85). Please change the 3rd SG device from SG z to SG x and then predict the outcome (including probability) after the third SG device. Please clearly state your reasoning/arguments. Note: SG z means Stern-Gerlach device measuring magnetic dipole moment m Z which o ...

  • 10 Pages


    Lehigh, PHYSIC 2

    Excerpt: ... Lecture-18 Lectures thus far covered: Electrostatics in vacuum and with dielectrics Magnetic fields due to electric current: a line current, a long solenoid, a toroid, a fat wire and a coaxial cable. Magnetic Field is non-conservative r r B dl = o I enclosed = o I i i Induced electric field due to changing B-flux Induced magnetic field due to changing E-flux Steady magnetic fields in vacuum: What happens if in material medium? Materials in Magnetic Field Experimental Fact: If an iron core is placed within a solenoid, the magnetic field becomes MUCH stronger. Different kinds of magnetic materials: Ferromagnetic; Paramagnetic; and Diamagnetic 1 Atomistic Origin of Magnetism Electron spin An electron has intrinsic spin r angular momentum S and associated spin magnetic dipole r moment , where s e r s = - S m r Note that S is quantum mechanical quantity. r Electron orbital magnetic dipole moment An orbiting electron inside an atom has orbital angular momentum Lorb and associ ...

  • 5 Pages


    Wisconsin, PHYS 202

    Excerpt: ... the direction of the force on each side? (Lecture 11 review: FB= ILxB ) FB=0 4 Torque on a Current Loop In Uniform B Field Exercise: For a current loop in a uniform B field, show that the torque on the loop is: |=IABsin (Quiz: In what direction?) r r r Conveniently, the result can be rewritten as: = IA B . 1 FB I I I 3 . . . . . . . . . I. . .1 . . . . . . . . 4 B X I 2 . .F. . . . . . . . . . . . . .F.B . . . B B I I 4 I I I 3 b 1 F4 a . . . . . . . . . . . . .2. . . . . . . . 3 . . Case 2 recall:FB=0 FB . I I 2 A x IA: magnetic dipole moment B F2 FB=0 bsin top view A : Area Vector Case 1 face view Magnetic Dipole Moment s N Magnetic dipole moment . S B Electric dipole moment p. + Review and Compare: Electric Dipole Moments +q -q - p= qd Macroscopic =IA IA F = 0 = B r U = - B in B Field r v Microscopic L angular momentum of orbiting or spin F = 0 = pE ...