LuduminaWA-03 · WA-U1 · Planned
Wave-speed investigations
Learning objectives
Choose suitable apparatus and methods for ripple-tank and solid waves; explain a method for sound speed in air.
8463 §§4.6.1.2;8.2.8 / 8464 §§6.6.1.2;10.2.20
DfE single-science pp.37–39 / Combined pp.32–33. Evidence checked 30 September–1 October 2026. Skills: WS2.3–2.7,3.1,3.5; MS2a,2b,3c.
Needs firstWA-02
Explanation
Measure several wavelengths or cycles to reduce relative reading uncertainty, then divide appropriately. A ripple tank and a vibrating solid need suitable separate methods. For an echo, the measured time includes travel to the reflector and back.
Concepts, equations and units: v=fλ or distance/time; m/s,Hz,m,s; multiple cycles/wavelengths reduce relative measurement error.
Prediction, demonstration and game exercise
Predict, observe, explain
Demonstrate ripple tank and vibrating string/solid apparatus plus sound timing/echo or microphone method.
Planned learner game exercise
Measure frequency/wavelength/speed in both required apparatus types; choose timing separation for sound.
Independent practice
Analyse repeat readings, compare methods and quantify one uncertainty; echo distance requires two-way path.
Original practice example · Shared
An echo returns in 0.40 s from a wall 66 m away. Find sound speed.
Show working and model answer
Working / reasoning
Total distance = 2 × 66 = 132 m; v = 132/0.40.
Answer
330 m/s.
Exit check and success criteria
Both RP apparatus contexts addressed with valid methods/data and a justified sound-speed method.
During practice, compare the prediction with evidence and give an error-specific prompt. The exit item uses a fresh context or fresh values, answered independently.
Misconceptions, practical links and mastery
Check these misconceptions
Only a ripple tank fulfils the RP; frame rate is actual wave frequency; echo travels only one way.
Practical preparation
RP-P8/RP-C20: waves in ripple tank AND solid. Sound-speed method is additional specified theory/practical knowledge; AT4.
Virtual preparation and revision only. Required hands-on activities and school records remain separate.
Proposed mastery
0: not yet evidenced. 1: supported. 2: independent exit criteria met. 3: successful changed-context transfer. Advance at 2; revisit with fresh retrieval. These are not GCSE grades.