A spring running horizontally has areas with the coils closer together and areas with them farther apart. A label A points to areas where they are closer together. A label B points to areas where they are farther apart. A label C sits near a bracket connecting the center of two successive areas with the coils farther apart, which are separated by an area of closer coils. Label the parts of the longitudinal wave.

Compressions:

Rarefactions:

Wavelength: