Electromagnetics doubt

by bhanesh
Tags: doubt, electromagnetics
bhanesh is offline
Dec14-13, 09:45 AM
bhanesh's Avatar
P: 9
Why j.ds has ' closed integral ' on below equation

Click image for larger version

Name:	1387035907054.jpg
Views:	24
Size:	23.8 KB
ID:	64772
Phys.Org News Partner Engineering news on Phys.org
Researchers propose network-based evaluation tool to assess relief operations feasibility
Large streams of data warn cars, banks and oil drillers
Engineering student developing traffic forecasts
phinds is offline
Dec14-13, 09:53 AM
PF Gold
phinds's Avatar
P: 5,676
It would probably be easier to tell if you posted the image right-side-up.

By the way, in English, what you have is not a "doubt", it is a question. See http://www.physicsforums.com/showthread.php?t=607274
Shyan is offline
Dec14-13, 09:55 AM
Shyan's Avatar
P: 734
I think this is some kind of continuity equation.Its considering a region of space with some charge inside it.Because charge can't be created or destroyed,the only thing which can cause the amount of charge to change is a current and so we should have a surface integral of current density.But because we're interested in a region of space,the surface is the one enclosing that region which is of course closed.

Register to reply

Related Discussions
Engineering Electromagnetics by Hayt or Electromagnetics with Applications by Kraus Electrical Engineering 3
electromagnetics Introductory Physics Homework 6
Electromagnetics ?'s Introductory Physics Homework 1
A.C Sonometer experiment Classical Physics 1
need help with electromagnetics Electrical Engineering 2