1. The problem statement, all variables and given/known data Two vibrating sources emit waves in the same elastic medium. 2. Problem This is just the beginning part of a question that goes into detail about speed, reflection, refraction, and angles of incidence. All of which I understand, but as usual, the easiest part of the problem is creating a huge mind block for me. I do not understand the exact definition of an elastic medium or medium, and if two sources are in it, how do they affect each other? 3. Attempt at solution I think a 'medium' refers to the general area that the waves travel through, but then if there are two different waves in the area are they overlapping or acting independently? My assumption is that the two waves act independently, but would be traveling at the same speed until they interact with another barrier. Thank you in advance to anyone whom can help.