>[!summary] Doppler shift explains the change in pitch > General formula: $f_l = \frac{v+v_L}{v +v_s} f_s$ > Speed in a medium $v = \sqrt{\frac{B}{\rho}}$ # Deriving Doppler Shift Doppler shift explain the change in pitch why the source of listener are moving relative to one another. ![[dop_1.png|500]] [^1] >[!note] Explanation Example of doppler shift for a moving body The general formula for Doppler shift is that of $f_l = \frac{v+v_L}{v +v_s} f_s$ where $v_l$ is the velocity of the listen and $v_s$ is the velocity of the source, and v is the speed of sound. The convention for determine whether $v_l / v_s$ is positive or negative is the convention of the direction of where listener to source. When the listener is stationary the $v_l$ is zero When the source is stationary $v_s$ is zero # Speed of Sound in a medium In any medium the velocity of sound can be found from the equation $v = \sqrt{\frac{B}{\rho}}$ [^1]: Taken from https://tikz.net/wave_doppler/ by Izaak Neutelings (December 2020) --- > 📚 Like this note? [Star the GitHub repo](https://github.com/rajeevphysics/Obsidan-MathMatter) to support the project and help others discover it! ---