I'm having some trouble understanding Kirchoff's loop law. I understand that it is a statement of conservation of energy, and I understand this. My problem comes when we start talking about circuit elements. If we had a shorted battery, the electrons moving through the circuit would loss there potential as they went around. Now lets add a resistor. The law states that the voltage lost in the resistor is equal to the emf of the battery. Why is this? To me it seems that the electrons lose their potential whether there is a circuit element there or not. How can we be sure that all the potential is lost in the resistor? Thank you for you help.