alright, so i got this potentional equation [tex] \Phi = k_e Q e^{-\alpha r}/r[/tex](adsbygoogle = window.adsbygoogle || []).push({});

it askes me to find the total charge after calcing the charge density, so

anyway...lets get the field [tex]\vec{E}=-\nabla \Phi[/tex]

so yea then take the divergence fot the charge density

[tex] \nabla \bullet \vec{E} = 4 \pi k_e p [/tex]

so then im assuming to figure out the "total charge" im gonna use the density in a volume intergral and equate that to [tex] 4 \pi k_e Q_{enclosed} [/tex] but what is my limit? is it is a sphere i can define by radius a as my surface? or what?

next question

finding the potential associated with a Vector field A by line intergration in polar cords (or any cords for that matter) whats that mean

[tex]\oint \vec{A} \bullet d\vec{r} = \Phi (b) - \Phi (a)[/tex] is that what they're talking about let me know

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# Homework Help: Total Charge what? potential by line inter

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