Wave Field Simulation
Experimental Parameters
Live Measurement Dashboard
Doppler Effect Verification
Real-time Analytical Graphs
Observation Data Table
| Trial | fₛ (Hz) | vₛ (m/s) | vₒ (m/s) | v_c (m/s) | fₒ (Hz) | Δf (Hz) | λ_front (m) | Status |
|---|
Guided Laboratory Procedure
Theory & Physics Reference
The Doppler Effect for Sound Waves
The Doppler Effect is the change in perceived frequency of a wave for an observer moving relative to its source. Named after Austrian physicist Christian Doppler, who described it in 1842.
1. General 1D Doppler Formula
Where v_c is the propagation speed of sound in the medium, v_o is observer velocity relative to the medium, v_s is source velocity relative to the medium, f_s is emitted source frequency, and f_o is observed frequency.
2. Spatial Wavefront Compression & Expansion
When a sound source moves through a medium, each wavefront expands spherically from the location where it was emitted. Because the source shifts position between consecutive emissions, wavefronts bunch up in front of the source and spread apart behind it:
3. Sign Conventions
- Approaching Motion: vₛ > 0 towards observer ⟹ denominator becomes smaller ⟹ fₒ > fₛ (Higher pitch).
- Receding Motion: vₛ < 0 away from observer ⟹ denominator becomes larger ⟹ fₒ < fₛ (Lower pitch).
- Observer Approaching: vₒ > 0 towards source ⟹ numerator becomes larger ⟹ fₒ > fₛ.