what measures volts
Â­TheÂ­ three most basic units in electricity are voltage (V), current (I, uppercase i) and resistance (r). Voltage is measured in volts, current is measured in amps and resistance is measured in ohms. A neat analogy to help understand these terms is a system of plumbing pipes. The voltage is equivalent to the water pressure, the current is equivalent to the flow rate, and the resistance is like the pipe size.