Integral of product of infintesimal volume

  • #1
I'm following the book ''introduction to electrodynamics by D.J. Griffiths''. As he has written that the formula ''integral of product of infintesimal volume with the square of electric field'' gives us the energy contained in a charge configuration that is always positive because we're encountering square.He has justified it by saying that it even considers the fabrication of charges and as we know the fabrication of point charge involves infinte energy.But why do i get a definite value when i calculate the energy of a charge configuration like spherical or cylindrical,rather if i'm following his argument correctly then in spherical,this formula should take into account of fabrication of all the charges and that's certainly infinite.what's that in his argument that i'm not getting?Please help!
 

Answers and Replies

  • #3
okay but what'd we get if we calculate the energy due to equal and opposite charges?should it be positive or negative?according to the formula statrd above,it'll always be positive.and using the formula [k(q1)(q2)]/r,it's negative.can you please justify how?
 
  • #4
Simon Bridge
Science Advisor
Homework Helper
17,857
1,654
Last edited by a moderator:

Related Threads on Integral of product of infintesimal volume

Replies
18
Views
2K
  • Last Post
Replies
4
Views
579
  • Last Post
Replies
2
Views
10K
Replies
4
Views
873
Replies
3
Views
642
Replies
5
Views
1K
Replies
25
Views
5K
Replies
2
Views
1K
Replies
13
Views
1K
Top