1. The problem statement, all variables and given/known data So you're being pushed on a swing by someone who is whistling at a constant 60Hz. At the bottom, Vmax is 4 m/s. Explain what you hear as you swing toward and away from the source of whistling (speed of sound is 343 m/s for this problem). 2. Relevant equations Observed frequency for someone moving toward and away from the source (I calculated the numbers correctly, it's the explanation that needs work). 3. The attempt at a solution I said that we know that at the bottom, you're moving at 4 m/s, so you can calculate the doppler shift only at that point. These shifts are 60.7Hz moving toward the source and 59.3Hz moving away from it. This demonstrates that, at this bottom point, you hear a higher frequency moving toward the source and a lower frequency moving away from it. This is my explanation so far, but I also need to account for the all of the other points in between and not just the bottom point and how the frequency varies in between. How can I do this?