I almost feel embarrassed to ask this. I've always understood it to be that the higher the frequency, the higher the energy (at least from what I've been taught). However, something has always bugged me: why then, when a medium is involved, are the lower frequencies the ones that make it through? Wouldn't this mean that the lower frequencies have more energy to perturb that medium? Examples of what I mean, Sound: If someone is blasting music in their car, or you walk outside past a night club, you hear the bass (lower frequency). Light: At sunrise/sunset, the sun looks yellow/gold because it has to travel through more atmosphere, deflecting the higher frequencies and only the lower frequencies (orange, yellow) reach you eyes. Perhaps this has to do with resonant frequencies but I'm not sure. Could someone explain the relationship between frequency and energy that explains this?