Progressive Waves (or) Travelling Waves

A wave that continues propagating through a medium in an ongoing, repeated fashion -- rather than a single isolated pulse -- is called a progressive wave or a travelling wave. This section develops the full description of such waves: their defining physical characteristics as a class, the mathematical wave equation that any genuine travelling wave must satisfy along with its standard sinusoidal solution, the two complementary graphical representations (plotting displacement against position at one instant, or against time at one position) used to visualise them, and finally the important distinction between the …