ELECTRICITY BLOG ( just for making our teacher happy) voltage, electric potential difference , electric pressure or electric tension is the difference in electric potential between two points. In the international system of units , the derived unit for voltage is named volt. In SI units, work per unit charge is expressed as joules per coulomb, where 1 volt = 1joule (of work) per 1 cuolomb (of charge) . Voltage is electric potential energy per unit charge , measured in joules per coulomb ( = volts). It is often referred to as "electric potential", which then must be distinguished from electric potential energy by noting that the "potential" is a "per-unit-charge" quantity Resistance is an electrical quantity that measures how the device or material reduces the electric current flow through it. T...