Voltage

The electrical potential difference that pushes current through a circuit.

Definition

Voltage is the measure of electrical pressure, in volts, that drives current through wiring. US residential service is typically 120V for outlets and 240V for large appliances.

In plain English

Voltage × amperage = wattage. Large appliances (dryers, ranges, EV chargers, central AC) require 240V circuits.

Example

A standard outlet provides 120V; an electric dryer outlet provides 240V.

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