 # Chapter 9. Magnetic Forces, Materials, and Inductance

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Chapter 9. Magnetic Forces, Materials, and Inductance
Forces on a Moving Charge The electric field effects an energy transfer between electrical field and partical The acceleration vector by the magnetic field is always normal to the velocity vector Steady magnetic field is incapable of transferring energy to the moving charge The force on a moving charge due to combined electric and magnetic fields Lorentz force equation: 목원대학교 정보통신공학전공

Force on a Differential Current
The force on a charged particle moving through a steady magnetic field Hall Effect Hall Voltage 목원대학교 정보통신공학전공

목원대학교 정보통신공학전공

Force between Differential Current Element
목원대학교 정보통신공학전공

목원대학교 정보통신공학전공

Force and Torque on a Closed Circuit
목원대학교 정보통신공학전공

목원대학교 정보통신공학전공

(magnetic dipole moment)
(uniform magnetic field) The torque on the current loop always tends to turn the loop so as to align the magnetic field produced by the loop with the applied magnetic field that is causing the torque. 목원대학교 정보통신공학전공

The Nature of Magnetic Materials
[Various types of materials in magnetic materials] Diamagnetic Paramagnetic Ferromagnetic Antiferromagnetic Ferrimagnetic Superparamagnetic 목원대학교 정보통신공학전공

Magnetization and Permeability
Bound charges: orbital electrons, electron spin, and nuclear spin. The current produced by the bound charges is called a bound current or Amperian current. 목원대학교 정보통신공학전공

목원대학교 정보통신공학전공

목원대학교 정보통신공학전공

Magnetic Boundary Conditions
목원대학교 정보통신공학전공

Magnetic Circuit 목원대학교 정보통신공학전공

Potential Energy and Forces on Magnetic Materials
In the electrostatic field, we first introduced the point charge and the experimental law of force between point charges. After defining electric field intensity(E), electric flux density(D), and electric potential(V), we were able to find an expression for the energy in an electrostatic field by establishing the work necessary to bring the prerequisite point charges from infinity to their final resting places. The general expression for energy is This is not as easily done for the steady magnetic field. We shall therefore merely present the result at this time. The total energy in a steady magnetic field in which B is linearly related to H is 목원대학교 정보통신공학전공

Inductance and Mutual Inductance
Define inductance ( or self-inductance) as the ratio of the total flux linkages to the current which they link. 목원대학교 정보통신공학전공

목원대학교 정보통신공학전공