Doppler Effect Acoustic Lab - Physics Simulations

t = 0.00s

Sound Source (S) Observer (O) Sound Waves

Live Telemetry & Summary

Observe the crowding of sound wavefronts. Adjust speeds to compress waves (higher pitch) or expand them (lower pitch).

Source Frequency (f_s):400 Hz

Perceived Frequency (f'):485.7 Hz

Frequency Shift (Δf):85.7 Hz

Variable Adjuster

Emitted Freq (f_s)400Hz

200600

Source Speed (v_s)60m/s

-150150

Observer Speed (v_o)0m/s

-100100

Acoustic Doppler Effect

DOPPL

The Doppler Effect describes the change in frequency of a wave in relation to an observer who is moving relative to the wave source. As the source moves towards the observer, wavefronts bunch up, shortening wavelength and raising perceived pitch. Moving away stretches wavefronts, lowering pitch.

f' = f_s \left( \frac{v \pm v_o}{v \mp v_s} \right)

Whiteboard Solver Steps

Step 1

Doppler Frequency Shift Equation

The observed frequency shifts higher when the relative distance decreases (moving towards each other) and shifts lower when distance increases.

f' = f_s \left( \frac{v + v_o}{v - v_s} \right)

Step 2

Frequency Shift Calculation

With the source traveling at 60 m/s and observer at 0 m/s, the shift in sound wave compression changes the perceived frequency by 85.7 Hz.

f' = 400 \text{ Hz} \left( \frac{340 + 0}{340 - 60} \right) \approx 485.7 \text{ Hz}