When a wave moves from a less dense to a dense medium... ?

Question

When a wave moves from a less dense to a dense medium and the wavelength DECREASES, does this mean that the graph of the wave will be "squished" or "stretched"?

Answer 1

A decreasing wavelength means that the peaks and valleys of the wave have less distance separating them.  Thus, the wave will appear squished.

Answer 2

The answer to this depends on what you are plotting on your X and Y axis. Time, frequency, wavelength, speed, and which is on plotted on each axis.