If there is only one resistor, the voltage drop is equal to the potential of the positive terminal. The voltage drop across more than one resistor is directly proportional to the value of each resistor. But the total drop in potential difference must be equal to the potential of the positive terminal. My question is - how do the electrons know that there are other resistors in the circuit and to only give part of their potential energy to some resistors and the rest to another?? Also, if the electrons are given potential energy from the power source, isn't that converted to kinetic energy to move them through the wires? How are they able to give energy to the resistors if they are using up their energy moving through the circuit? If a circuit was set up without any resistors at all, where does the energy go??