Question

correctly label the diagram of the longitudinal wave below. (not all choices will be used)

diagram of longitudinal wave with yellow boxes for labels

crest wavelength trough
rarefaction compression amplitude

Explanation:

1. Top left box (wide-spaced lines): This region has particles spread apart, which defines a rarefaction in a longitudinal wave.
2. Top right box (closely spaced lines): This region has particles packed tightly together, which defines a compression in a longitudinal wave.
3. Bottom box (one full wave cycle): This spans one complete rarefaction and one complete compression, which is the definition of a wavelength for a longitudinal wave.

Crest, trough, and amplitude describe transverse wave features, not this longitudinal wave, so they are unused.

Answer:

• Top left yellow box: rarefaction
• Top right yellow box: compression
• Bottom yellow box: wavelength