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Home Concept Builders Vibrations and Waves Wavelength Help Help 2

Wavelength - Questions 2 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:

Determine the number of crests and troughs in the following transverse wave patterns.

As a transverse wave moves through a medium, the particles of the medium vibrate back and forth about a fixed position known as the resting position. The resting position is the grey line shown in the diagram. Each particle moves between two extremes - the crest and the trough. The crest is the highest position and the trough is the lowest position. You might say that the crest is the position at which a particle has a maximum positive displacement and the trough is the position at which a particle has maximum negative displacement. Success in this question demands that you accurately count the crests (highest positions) and the troughs (lowest positions).

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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