1. The problem statement, all variables and given/known data Show that the energy of an ideal dipole in an electric field E is given by: U = -p [itex]\bullet[/itex] E 2. Relevant equations The energy required to bring to charges together, their electrostatic energy, is: W = ½ ƩqiV(ri) 3. The attempt at a solution Well I want to know what the energy cost is of taking in the dipole. Because if you take in one charge first then the energy cost will be negative (as they attract each other). But if you see the dipole as already bounded before taking it in then the cost will be nothing. Hence: Is the above formula even correct to apply?