Hi everyone, I got a little question. Let's say we have 3 point charges on a line, for example on the x axis. 1----2----3 something like this. If I want to calculate the Force on point charge one, why am I allowed to just add the forces 12 and 13. I saw it in a book and was confused. Why don't I have to consider the interaction between the particel 2 and 3? Thanks for your help.