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Home Concept Builders Vibrations and Waves Wavelength Help Help 4

Wavelength - Questions 4 Help

As a wave passes through a Slinky, coils of the Slinky begin to vibrate about their usual position. They can vibrate perpendicular to the Slinky, leading to the formation of crests (highest points) and troughs (lowest points). Or they can vibrate parallel to the Slinky, leading to the formation of compressions (coils pressed together) and rarefactions (coils spread apart).

There are three similar versions of this question. Here is one of those versions:
 

Version 1:

Identify the rarefactions in the following longitudinal wave patterns.

As a longitudinal wave moves through a Slinky, the coils of the Slinky vibrate back and forth about a fixed position known as the resting position. The direction of the particle motion is parallel (and anti-parallel) to the Slinky. At any given moment in time, there will be regions along the Slinky where the coils are pressed together very closely. These regions of maximum closeness are known as compressions. There are also regions where the Slinky coils are spread apart with a maximum separation distance. These regions are called rarefactions. In this question, you must count the rarefactions - the spaced-apart regions.

Try this link to The Physics Classroom Tutorial for more help with the concept of wavelength:

The Anatomy of a Wave

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