What is wavelength

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Frequency and wavelength are both properties of waves. They are closely related, so this article discusses the two together.

Frequency is the number of repeated motions in a period of time.

These motions can be up and down, like a hammer, or back and forth, waving a hand. Or some other repeated motion, maybe the swinging of a pendulum.

Wavelength unit

Wavelength unit

Frequency symbol

Frequency to wavelength calculator

What is the relationship between frequency and energy

Wavelength symbol

Repeated motions are called “oscillations” or “cycles.” So, frequency is the number of cycles per unit of time, often measured in seconds.

Cycles can be graphed on paper, as in the accompanying image.

In the case of the up and down motion of the hammer, the vertical axis would be elevation and the horizontal axis would be time. When the hammer is highest in elevation, it’s a crest. When it’s lowest in elevation, it’s a trough.

What is the relationship between frequency and energy

Then, over time, the hammer rises again in elevation to a crest, and so on.

In this image, frequency is the number of cycles, crest to crest, completed in a second. Or the number of motions, trough to trough—same thing.

The more cycles per second, the

how is wavelength related to frequency of a longitudinal wave

how is wavelength related to frequency in a wave