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32 Magnetism of Matter:Maxwell ’ s Equations. 32-1 Magnets. The simplest magnetic structure that can exit is a magnetic dipole.Magnetic monopoles do not exist(as far as we know). 32-2 Gauss ’ Law for Magnetic Fields. 32-3 The Magnetism of Earth. 32-4 Magnetism and Electrons.
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32 Magnetism of Matter:Maxwell’s Equations 32-1 Magnets The simplest magnetic structure that can exit is a magnetic dipole.Magnetic monopoles do not exist(as far as we know)
32-4 Magnetism and Electrons Spin Magnetic Dipole Moment
32-5 Magnetic Materials Diamagnetism Paramagnetism Ferromagnetism
32-6 Diamagnetism A diamagnetic material placed in an external magnetic field develops a magnetic dipole moment directed opposite .If the field is nonuniform,the diamagnetic material is repelled from a region of greater magnetic field toward a region of lesser field.
32-7 Paramagnetism A paramagnetic material placed in an external magnetic field develops a magnetic dipole moment in the direction of .If the field is nonuniform,the paramagnetic material is attracted toward a region of greater magnetic field from a region of lesser field.
Magnetic Domains A ferromagnetic material placed in an external magnetic field develops a strong magnetic dipole moment in the direction of If the field is nonuniform,the ferromagnetic material is attracted toward a region of greater magnetic field from a region of lesser field.
Sample Problem 32-2 needle’s mass Step one: N= iron’s atomic mass iron’s Atomic= mass iron’s molar mass M Step two: Acogadro’s number NA
mNA Step three: N= M needle’s mass m Step four: =(needle’s density)(needle’s volume) =(7900kg/m3)(1.5×10-8m3) =1.185×10-4kg Step five:
Sample Problem 32-3 (a) Step one: Step two:
Step three: Step four:
(b) (c)
Sample Problem 32-4 (a) Step one: Step two:
Step three: Step four:
(b) Step one: Step two:
32-11 Maxwell’s Equations Gauss’ law for electricity Gauss’ law for magnetism
Faraday’s law Ampere-Maxwell law 主菜单