Wave machine
Adjust frequency, amplitude and wave speed, and read wavelength straight off the display. Compare transverse and longitudinal waves.
- v = fλ
- Amplitude and wavelength
- Transverse vs longitudinal
Speed
200m/s
Frequency
2.0Hz
Wavelength
100m
Time period
0.5s
Predict
If the frequency doubles while the wave speed stays the same, what happens to the wavelength?
Experiment
- 1Fix the speed at 200 m/s and double the frequency. Read the new wavelength.
- 2Change only the amplitude. Confirm the wavelength readout does not move.
- 3Switch to longitudinal and find the compressions — the regions where the dots bunch up.
Explain
A wave transfers energy without transferring matter. In a transverse wave the oscillations are perpendicular to the direction of energy transfer; in a longitudinal wave they are parallel, giving compressions and rarefactions.
The three quantities are locked together by v = f λ. Amplitude is independent — it sets how much energy the wave carries, not how fast or how long it is.
This is also why refraction works the way it does: the frequency is fixed by the source, so when the speed changes at a boundary the wavelength has to change with it.