clear all; close all; qA=-2; qB=1; rA=[2,1,0]'; rB=[0,1,0]'; r=[rA rB]; e0=8.85*1e-12; k = 1/4/pi/e0; F = k*qA*qB/sqrt(sum((rA-rB).^2)); Fdummy=1;%correction for view F=Fdummy;%The real F is too huge to be shown, so just leave it v=rA-rB; …