Properties of Electricity
Several properties of electricity must be understood in order to understand electrosurgery. Electrons orbit the nuclei of atoms. Current flow occurs when electrons flow from one atom to the orbit of an adjacent atom. Voltage is the "force" or "push" that provides electrons with the ability to travel from atom to atom. If electrons encounter resistance, heat will be produced. The resistance to electron flow is called impedance.
A completed circuit must be present in order for electrons to flow. A completed circuit is an intact pathway through which electrons can travel. In this diagram, voltage is generated by the power plant, providing the force to push electrons through the circuit. The original source of these electrons is the earth (ground).To complete the circuit the electrons must return to ground. Any grounded object can complete the circuit - allowing the electrons to flow to ground.