Doppler Frequency Calculator

Calculate the observed frequency due to the Doppler effect: f_obs = f_source * (c + v_observer) / (c + v_source), with sign convention for approach/recession.

Hz
m/s
m/s
m/s

Observed Frequency

404.6113 Hz

Frequency Shift-35.3887 Hz

Observed Frequency vs Source Frequency

Voir la formule →

Formule

## Doppler Effect for Sound The Doppler effect shifts the observed frequency when the source or observer is moving relative to the medium. ### Formula **f_obs = f_s * (c + v_obs) / (c + v_src)** Sign convention: v_obs is positive when moving toward the source; v_src is positive when moving away from the observer. - Source approaching: lower denominator, higher f_obs - Source receding: higher denominator, lower f_obs

Exemple Résolu

A 440 Hz siren moves away at 30 m/s, observer stationary.

  1. 01f_obs = 440 * (343 + 0) / (343 + 30)
  2. 02f_obs = 440 * 343 / 373
  3. 03f_obs = 440 * 0.9196
  4. 04f_obs = 404.6 Hz (lower pitch)