National League for Nursing (NLN) Science Practice Exam

In the context of waves, what is the relationship between speed, frequency, and wavelength?

1. Speed = Frequency × Amplitude

2. Speed = Frequency × Wavelength

3. Speed = Wavelength × Amplitude

4. Speed = Frequency + Wavelength

The correct answer is: Speed = Frequency × Wavelength

The relationship between speed, frequency, and wavelength in wave mechanics is defined by the equation: Speed = Frequency × Wavelength. This fundamental equation illustrates how the speed of a wave is directly proportional to both its frequency and its wavelength. In this context, frequency refers to the number of wave cycles that pass a given point per unit of time, typically measured in hertz (Hz). Wavelength is defined as the distance between two successive points of the same phase on consecutive waves, such as crest to crest or trough to trough, and is usually measured in meters. Thus, when you multiply frequency (in Hz) by wavelength (in meters), you obtain a speed that is typically expressed in meters per second (m/s). This equation is essential in various fields, including physics, engineering, and acoustic studies, as it allows for the calculation of how fast a wave travels through a medium. The other options do not accurately reflect the relationship between speed, frequency, and wavelength, as they include incorrect variables or operations that do not hold true in wave dynamics. For instance, amplitude—a measure of wave height—does not figure into this fundamental relationship, nor do addition or multiplication with it correctly represent the mechanics of wave behavior.