Hertz

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Hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI). It is defined as one cycle per second. The unit is named after the German physicist Heinrich Hertz, who made significant contributions to the study of electromagnetic waves.

Definition

One hertz represents one cycle per second. The SI unit is used to measure the frequency of periodic phenomena, such as sound waves, radio waves, and light waves. For example, a sound wave with a frequency of 50 Hz completes 50 cycles in one second.

History

The unit was established in honor of Heinrich Hertz, who was the first to conclusively prove the existence of electromagnetic waves. His experiments in the late 19th century confirmed the theories of James Clerk Maxwell.

Applications

Hertz is used in various fields, including:

• Acoustics: Measuring the frequency of sound waves.
• Electronics: Describing the frequency of oscillators and signal processing.
• Radio: Defining the frequency of radio waves, which are used in communication systems.
• Computing: Measuring the clock speed of central processing units (CPUs).

Multiples and Submultiples

The hertz can be expressed in multiples and submultiples:

• Kilohertz (kHz) - 1,000 Hz
• Megahertz (MHz) - 1,000,000 Hz
• Gigahertz (GHz) - 1,000,000,000 Hz
• Millihertz (mHz) - 0.001 Hz
• Microhertz (µHz) - 0.000001 Hz

Related Concepts

• Frequency
• Wave
• Electromagnetic spectrum
• Sound
• Radio frequency
• Signal processing

See Also

• Heinrich Hertz
• James Clerk Maxwell
• Electromagnetic wave
• International System of Units