hi, guys: Charge conservation Violated? It seems to be: The charge density inside a spherical volume changes from [tex]\rho[/tex] at t=0, after period of time [tex]\tau [/tex], the charge density decrease to 0. However, the author claimed that during the processing there is no current density in the material surrounding the initially charged spherical region. Is this possible? I am now reading a something about Charge Relaxation in a conductor. You can find the example in the following way: Click on the weblink:http://web.mit.edu/6.013_book/www/book.html Then click chapter 7 on the left column , the whole index of chapter 7 will appear on the right; After that, you click on the section 7.7; At last, you go to the example 1. where you see what I want to talk about. Note: Equation (7.15) can be found in the following weblink http://web.mit.edu/6.013_book/www/book.html click on Chapter 7 on the left column, and then click on the section 7.1 on the right column In the example it states that: " one or both of these migrate in the electric field caused by the net charge[in accordance with (7.15)] while exactly neutralizing each other" Anybody agree with this? Can he/she give some explanation?