M.5 Chapter 3 Waves

Simulation window

Paused — make a prediction first

🖱️ เครื่องจำลองคลื่นในเส้นเชือก 3 มิติ (3D Wave Machine): หมุน 360° | ซูมเข้า-ออก | สังเกตการสะท้อนที่ปลายสาย

ModeContinuous

End boundaryFixed

Amplitude24 cm

Frequency1.0 Hz

Tension / medium factor1.0×

Damping0.00

show measurements

Wave speed v

1.20 m/s

Wavelength λ

1.20 m

Period T

1.00 s

Reflection sign

−1

Model:

v = 1.2 \sqrt{η} m/s

•

v = f λ

•

f = \frac{1}{T}

speed = 1.2 × √(η) m/s • speed = frequency × wavelength • frequency = 1 ÷ period

Participation mission

Work in pairs: one person controls, one person records. Swap after each mission.

MeasureSet the frequency to 1.0 Hz. Read the wavelength from the ruler, then calculate the speed.

Predict the boundaryChoose a fixed or loose end. Predict the reflection before pressing Play.

Defend a claimChange tension only. Explain what happens to speed while frequency stays fixed.

Evidence checklist

I wrote a prediction before playing. I changed one variable at a time. I recorded units with my measurement. I used a sketch + equation + observation.

Teacher move: pause the simulation at the boundary and ask, “What changed: speed, direction, displacement sign, or more than one?”

Evidence log

Claim → setting → measurement → observation → reasoning

Wave Lab: see it, measure it, explain it