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vector poynting

jnecochea
1-Newbie

vector poynting

i have a problema with Delta while i am writting a vector poynting

I am writing the Poynting Vector and i have a problema with delta in the  equation F1 and a5, a2, a6

Captura1.PNGCaptura2.PNG

thank you for your help

1 ACCEPTED SOLUTION

Accepted Solutions
-MFra-
21-Topaz II
(To:jnecochea)

10 REPLIES 10
-MFra-
21-Topaz II
(To:jnecochea)

It is unclear which version of Mathcad you are using . If you're referring to the impulse of Dirac, it is a special function of an independent variable. In your formula appears only the delta symbol. Instead, you should write a function. If, moreover, the symbol delta, is referred to any increase , it must have been previously defined so that the formulas give a result.

To get a result from your equations, you have to use the appropriate symbol of  equality, ie that corresponding to the assignment (obtained with a colon).

The Bessel functions must be written according to the definition of Mathcad, ie: J0 (x), Jn (n, x), K0 (x), Kn (n, x), ...

Necochea.jpg

Hi.

Poynting vector is S = 1/μ E x B. As you subscript it with z1, it's assumed that E = (E,0,0) and B = (0,B,0). But in your expression can't identify E nor B.

Also, what are J and K? Bessel functions? If that, in Mathcad you don't have J2, but have Jn with two args. And for K2 must to write your own Bessel function.

For functions in general, you must to write exponents as (J.1(UR))^2, but not J.1^2(UR).

From the fisrts equations, those for a,b and F you can't derive S, at least without explain from where came R, n1 or phi.

Finally, Delta seems to be a small displacement from some equilibrium position, and guess that it is the small of the problems for write the equation for the Poynting vector.

Best regards.

Alvaro.

-MFra-
21-Topaz II
(To:AlvaroDíaz)

Hi Alvaro,

precisely:

Poynting.jpg

RichardJ
19-Tanzanite
(To:jnecochea)

Could you please post a worksheet. Without a worksheet we can only guess what your problem actually is.

Hello eveyone

Can I solve the problem, but i can´t graph Sz2 in the same plot where is Sz1

help me please

RichardJ
19-Tanzanite
(To:jnecochea)

Sorry, I can't open a Prime 3.1 file, and that is true for many others on these forums. Could you post it as a pdf please.

PDF attached.

-MFra-
21-Topaz II
(To:jnecochea)

poynting0.jpg

hello everyone

If Sz1 and Sz2 have the same units, why can´t i plot Sz2 in the same graph?

the massage is: "No se puede trazar esta función. Se debe evaluar en valores reales", "You can not draw this function. Must be assessed in real terms"

i need to work Sz1 with 0 < r < a and with Sz2 with a <= r < infinite.

how can i add that ruler in the equation?


than you for your help

-MFra-
21-Topaz II
(To:jnecochea)

Conduttanza.jpg

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