Physics HL · Chapter 15: Standing Waves and Resonance
Chapter 15 Wrap-Up
Consolidate standing-wave and resonance problem solving into one repeatable sequence from boundary setup to quantitative response interpretation.
Estimated time: 12 minutes
Exam Workflow for Standing Waves and Resonance
Start by classifying the system: bounded-wave mode (string/pipe) or driven oscillator response (resonance graph). For bounded modes, write end conditions, sketch the simplest allowed mode, then generalize to harmonic n. For resonance, identify natural frequency, damping level, and the location/shape of the response peak before calculating.
Keep one consistency check at the end of each problem. If your mode index rises, wavelength should decrease for fixed length. If damping rises, resonance peak should flatten. If your final numbers violate these trend checks, revisit boundary classification or harmonic indexing before submitting.
Chapter 15 Key Takeaways
- Standing waves arise from superposition of equal opposite traveling waves.
- Node-node spacing is lambda/2; node-antinode spacing is lambda/4.
- Fixed-fixed strings and open-open/closed-closed pipes share lambda_n = 2L/n.
- Open-closed pipes support odd harmonics only, with lambda_n = 4L/n for n = 1, 3, 5, ...
- Driven oscillation amplitude depends on frequency match and damping level.
- Higher damping lowers, broadens, and slightly left-shifts the resonance peak.
No new simulation is added in this wrap-up because this stage is synthesis. Revisit the chapter lab in each mode and run a prediction-check loop: state expected node/antinode geometry or resonance-curve shift first, then verify with parameter sweeps.