' File FieldA5x - - Electric Force :  2 Charges with potential curves.

qa = 5  :  xa = 3  :  ya = 3 
qb = -5 :  xb = -3 :  yb = -3

Ra{x,y} = Sqrt[(x - xa)^2 + (y - ya)^2]
Rb{x,y} = Sqrt[(x - xb)^2 + (y - yb)^2]

Ex{x,y} =  qa*(x - xa)  / Ra{x,y}^3  +  qb*(x - xb)  / Rb{x,y}^3
Ey{x,y} =  qa*(y - ya)  / Ra{x,y}^3  +  qb*(y - yb)  / Rb{x,y}^3

G{x,y} =  -1 / sqrt[Ex{x,y}^2 + Ey{x,y}^2]

a = -10  : b = 10 : n = 14
c = -10  : d = 10 : m = 14

PlotDirField[Ex, Ey, {a,b,n}{c,d,m}]

x1 = -2:  y1 = 2:  x2 = -3:  y2 = -3
PlotSlopeField[G, {a,b,n}{c,d,m} {x1, y1}]



