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Fundamental definitions and relations

1) dielectric Constant in the empty one:

 

2) magnetic Permeability in the empty one:

 

3) Carrier dielectric movement:

 

4) Carrier magnetic field:

 

5) Theorem of the divergence:

The flow of carrier X through one surface S sluice is equal to the calculated divergence of X on the volume enclosed from S:

6) Theorem of Stokes:

The flow of the rotor of one carrier X through one open surface S is equal to the calculated circuitazione of X along the frontier l of S:

7) Theorem of Coulomb:

The carrier dielectric movement D in a point in proximity of a conductor is worth being s the density of loads in proximity of the point p. If s> 0 then z0 indicate the outgoing normal school otherwise it indicates the entering normal school.

8) Law of Faraday:

9) Law of Ampere:

it is worth alone in the stationary case otherwise must be held account also of the movement current.

 

10) Law of Gauss:

11) Relations of Maxwell:

the divergence characterizes sources of the field while the rotor characterizes if the field is conservativo or less.

 

12) Equation of continuity:

that is also a variation of the density of loads can generate one density of J current.

 

13) Current of movement:

that is the flow of the density of current of outgoing movement from the S surface is equal to the flow of the density of current of conduction entering in the same one.

 

14) Parameters that characterize means:

to)       the dielectric constant and

b)       magnetic permettività m

c)       the conductivity electrical worker g

 

15) homogenous Means:

The parameters that characterize means are independent from the position.

 

16) linear Means:

The parameters that characterize means do not depend on the intensity of the fields.

 

17) Means isotropo:

The parameters that characterize means do not depend on the direction of the fields.

 

18) chirale Means:

The carriers magnetic electrical workers and depend on the correspondents carriers of both the types ossia and also being toc the chiralità admittance.

 

19) comprehensive Equations of Maxwell of sources:

where J represents one current impressa due to the transformation of energy from a frequency to an other while Jim is one magnetic current impressa that the equivalence theorem demonstrates to be symmetrical to the current electrical worker impressa J while J comes introduced for simmetrizzare the two equations and to be able to apply the dualità.

 

20) Dualità:

Once inserted the currents impresse in the 1ª and 2ª the equation of Maxwell, these become symmetrical and by means of the changes of variable:

it can be passed from one to the other or also, to pass from the solution of one equation to the solution of the other.

 

21) Ties for the normal members of the fields:

A having cylinder is considered the bases in two means characterizes you from various parameters, and the body in the transition zone, applying the theorem of Gauss has , the surface integral can be subdivided in an integral on the inferior surface S1 , an integral on the advanced surface S2 and on the lateral surface S3 , this last one stretches to zero when the height of the cylinder is reduced while the others two end in order to only differ for the sign, after all has where 2° the member is worth 0 if r it is ended while it is worth s if as it happens in the case of an ideal conductor for which ha the .

 

22) Ties for the tangential members of the fields:

A having coil is considered the inferior side contained in means and the contained advanced side in other means while the height is contained in the transition zone. Calculating the flow of 2ª the equation of Maxwell ha to 1° the member the theorem of Stokes obtaining can be applied, this last circulation can be subdivided on 4 coppers of the coil and when if ago to stretch some to zero the height has where the 2° member it is worth 0 if J is ended while it is worth K if as it happens in the case of an ideal conductor for which ha the .