Hertz (Hz)

Quantity: Frequency · Category: Derived SI

The hertz is the SI unit of frequency: one cycle per second. It measures how often a repeating event occurs — named after Heinrich Hertz, who first demonstrated radio waves.

Relation to SI

1 Hz = 1 /s (one cycle per second)

Examples

• Mains electricity alternates at 50 or 60 hertz.
• An FM radio station at 100 MHz oscillates 100 million times per second.