 The applied voltage (kV) accelerates these electrons toward an anode target, ultimately producing x-rays when the electrons are stopped in the anode.Thus, the kVp corresponds to the highest kinetic energy of the electrons striking the target, and is proportional to the maximum energy of the resulting X-ray emission spectrum.In early and basic x-ray equipment, the applied voltage varies cyclically, with one, two, or more pulses per mains AC power cycle.