What is the relationship between frequency and wavelength?

The relationship between frequency and wavelength is fundamentally governed by the wave equation, which states that the speed of a wave is equal to the product of its frequency and wavelength. This relationship is expressed mathematically as:

[ \text{Speed} = \text{Frequency} \times \text{Wavelength} ]

In the context of ultrasound and similar phenomena, while the speed of sound in a given medium is relatively constant, frequency and wavelength exhibit an inverse relationship. When frequency increases, the wavelength decreases, provided that the speed of sound remains unchanged. This inverse proportionality means that if you know the speed of sound, you can determine that increasing the frequency will lead to a shorter wavelength, and conversely, a lower frequency will result in a longer wavelength.

This inverse relationship is critical in various applications of sonography, as different frequencies are used for different imaging purposes, affecting resolution and penetration depth. Understanding this concept is essential for sonographers to make informed decisions about the parameters they choose while performing ultrasound examinations.