Doppler effect for sound waves

Need to know

What you need to know

• $f_o$: The observed frequency detected by the listener.
• $f_s$: The actual frequency emitted by the sound source.
• $v$: The speed of sound in the surrounding medium (e.g., air).
• $v_s$: The speed of the sound source relative to the medium.
• Use the **minus sign ($-v_s$)** in the denominator when the source is moving *towards* the observer (results in a higher $f_o$).
• Use the **plus sign ($+v_s$)** in the denominator when the source is moving *away* from the observer (results in a lower $f_o$).

Explanation

Doppler effect for sound waves

1. $f_o$: The observed frequency detected by the listener.
2. $f_s$: The actual frequency emitted by the sound source.
3. $v$: The speed of sound in the surrounding medium (e.g., air).
4. $v_s$: The speed of the sound source relative to the medium.