Click start to place several charges on the field. Then rearrange them so that the net flux out of the top of the box (as measured by the field lines) is twice that out of the bottom, with the same sign.

What are the coordinates of each of the charges? (e.g. "charge 1 (1.1,-0.7)")

Can you find any arrangement where the net number of flux lines is out of the box?




Physlet problem authored by Scott Bonham and modified by Wolfgang Christian.