Resistors slow down the electrons flowing in its circuit and reduce the overall current in its circuit. The high electron affinity of resistors' atoms causes the electrons in the resistor to slow down. These electrons exert a repulsive force on the electrons moving away from the battery's negative terminal, slowing them. The electrons between the resistor and positive terminal do not experience the repulsive force greatly from the electrons near the negative terminal and in the resistor, and therefore do not accelerate. Read more