What are "compressions" in longitudinal waves?

In longitudinal waves, compressions are the areas where the particles of the medium are closest together. This phenomenon occurs as the wave moves through the medium, leading to a series of alternating regions of high pressure (compressions) and low pressure (rarefactions). During compressions, the particles in the wave collide and are densely packed, resulting in high energy transfer.

This distinction is essential when analyzing wave behavior. By understanding that compressions correspond to locations of maximum particle density, one can better visualize how sound waves, for instance, propagate through different materials. The spacing of particles in the compressions directly influences the characteristics of the wave, such as its speed and intensity. Having a clear grasp of this concept is vital for further studies in wave mechanics and their applications.