voltage

Everyday

1. Voltage is the push that makes electric current flow around a circuit. tree →
2. Voltage is measured in volts (V); a higher voltage gives a bigger push. tree →

In the lessons

In science lessons on electricity, a battery marked 1.5 V has a voltage of 1.5 volts; adding more cells in a line raises the voltage and makes a bulb brighter. In safety lessons mains electricity has a high voltage and is dangerous; never touch sockets or wires with wet hands. Signs say «Danger: High Voltage».

Examples

• The battery has a voltage of 9 volts. tree →
• Two 1.5 V cells give a voltage of 3 V. tree →
• Higher voltage made the bulb shine brighter. tree →
• Danger: high voltage — keep out! tree →
• Mains voltage in the UK and Australia is about 230 volts. tree →
• We measured the voltage with a voltmeter. tree →
• Too much voltage can blow a bulb. tree →

Note

Measured in volts, symbol V. In maths/science: cells in series add their voltages (1.5 V + 1.5 V = 3 V). Do not confuse voltage (push) with current (flow, measured in amps).