volt

Everyday

1. A volt is the unit used to measure voltage, the "push" that makes electricity flow around a circuit. tree →
2. The short form is V: a 1.5 V battery. tree →

In the lessons

In science lessons on electricity, batteries (cells) have a voltage marked on them: AA cells are 1.5 volts; more cells in a series give more volts and make a bulb brighter or a buzzer louder. In the UK, mains electricity is about 230 volts, in the USA about 120 volts — dangerous, so never poke anything into sockets. The volt is named after the Italian scientist Alessandro Volta, who made an early battery. Phrases: «1.5-volt battery», «high voltage», «volts and amps».

Examples

• An AA battery gives 1.5 volts. tree →
• Two 1.5-volt cells in series make 3 volts. tree →
• Mains electricity in Britain is about 230 volts. tree →
• The sign said "Danger: high voltage". tree →
• The bulb shone brighter when we added another volt. tree →
• The volt is named after Alessandro Volta. tree →

Note

Symbol: V (capital). Plural: «volts». Maths: in a series circuit, add the volts of each cell: 1.5 + 1.5 + 1.5 = 4.5 V. «Voltage» is the quantity; «volt» is the unit, like «length» and «metre». Do not confuse with «vault» (a jump or a safe room).