At a certain distance r l'rorn an infinitely long straight conductor with a unlforml y distributed l i nnar charge 't there is a dipolo with an electric moment Pel directed along the Ii no of Iorce represeul.ing the field generated by the conductor at the point where the dipole is located. Assuming the arm of the dipole is very small compared to the distance r, Iind the Iorce with which the field acts on the dipole.