Today I was presented with dispersion in my introductory physics class. Before this topic was presented we were told of two important rules for waves: 1) The speed of a wave is dependent on the medium in which it travels and 2) the frequency of wave does not change when going from one medium to another. Now back to dispersion. I am able to see several trends from dispersion: EM waves with higher frequencies and therefore higher energy will travel slower in a medium and therefore bend more towards the normal. Now rule 1 is clearly violated here because there seems to be a inverse relationship between the frequency of a wave and its speed in a medium. To resolve this I though well, EM waves are special in that their energy is directly proportional to their frequency. Therefore, perhaps the reason the EM waves end up traveling slower in a medium based on their frequency is a direct result of their energy which makes sense since the only reason EM waves slow down in a medium is due to the atomic interactions of photons with electrons in the medium resulting in a cycle of absorption and emission. With this in mind, the natural question that came into mind was will the relationship between speed and energy also hold for other waves? Let's consider sound waves. Well there are no photons there but sound waves are due to the the pressure of molecules. So let's sound there was a sound wave in a Helium medium and a sound wave in a Fluorine medium and that both these sound waves were traveling at the same speed. The Fluorine medium sound waves would therefore have a greater kinetic energy since they have greater mass. Now let's say these two sound waves were to be transmitted through the ocean. Would the sound wave in Fluorine bend more towards the normal and ultimately travel slower does this not make any sense?