Electromechanical Dynamics (Part 1).0028

# Electromechanical Dynamics (Part 1).0028 - where 1o is the...

This preview shows page 1. Sign up to view the full content.

Electromagnetic Theory Symbols and Units of Electromagnetic Quantities Field Variable Name Magnetic field intensity Free current density Free surface current density Magnetic flux density Magnetization density Electric field intensity Electric displacement Free charge density Free surface charge density Polarization density Force density Permeability of free space Permittivity of free space MKS Rationalized Units A/im A/m 2 A/im Wb/m2 A/m V/m C/m 2 C/m 3 C/m 2 C/m2 N/m 3 47r x 10 - 7 H/m 8.854 x 10 - 1 2 F/m properties of the materials affect the field and source quantities. The magneti- zation density M is introduced to account for the effects of magnetizable materials. The most common constitutive law for M takes the form M = XmH, (1.1.6) where Z, is the magnetic susceptibility. An alternative way of expressing this relation is to define the permeability ~ = u,(l + X,,),
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: where 1o is the perme-ability of free space ou, = 47r x 10- 7 H/m, (1.1.7) in which case it follows from (1.1.4) that the constitutive law of (1.1.6) can also be written as B = uH. (1.1.8) We shall make considerable use of this simple linear model for magnetizable materials. Free currents in a stationary material most often arise from conduction induced by the electric field according to Ohm's law: Jf = oE, (1.1.9) where a is the conductivity (mhos/m). A similar constitutive law relates the surface current density K, to the electric field intensity E, tangential to the surface K, = rsEt, (1.1.10) where ar is the surface conductivity (mhos). These constitutive laws for the Table 1.1 Symbol H Jf K, B M E D Pf af P F Eo0 A-PDF Split DEMO : Purchase from www.A-PDF.com to remove the watermark...
View Full Document

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern