/ˈvoʊltɪdʒ/

noun … “Electrical potential difference between two points.”

Voltage is the measure of electric potential energy per unit charge between two points in a circuit. It represents the force that drives electric charges to move through a conductor, creating current. Voltage is fundamental to understanding and designing electrical and electronic systems.

Key characteristics of Voltage include:

  • Unit: measured in volts (V).
  • Polarity: has positive and negative terminals indicating direction of potential difference.
  • Source types: can be supplied by batteries, generators, solar cells, or power supplies.
  • AC vs DC: can alternate in direction (AC) or remain constant (DC).
  • Relation to energy: energy delivered to a charge is the product of voltage and charge (E = V × Q).

Applications of Voltage include powering circuits, driving motors, charging batteries, and controlling electronic devices. Understanding voltage is essential for calculating current, resistance, and power in circuits.

Workflow example: Calculating current using Ohm's law:

resistor = 1000   -- Ohms
voltage = 5       -- Volts
current = voltage / resistor
print(current)    -- 0.005 A

Here, voltage drives current through the resistor according to Ohm’s law.

Conceptually, Voltage is like water pressure in a pipe: it determines how strongly charges (or water) are pushed through the system.

See Current, Resistance, Power, AC, DC.