Waves
Method overview
Generate steady waves. Measure distance across several wavelengths and divide; measure frequency from generator; calculate v = fλ. Repeat for different conditions while controlling the medium.
Apparatus set-up
Diagramripple tank; signal generator; lamp; ruler; strobe; string; vibration generator
Independent variable
frequency or tension
Dependent variable
wavelength and wave speed
Control variables
water depth; amplitude; measurement region; string length/tension as appropriate
Apparatus
ripple tank; signal generator; lamp; ruler; strobe; string; vibration generator
Safety
Keep water away from electrical equipment; use low-voltage apparatus; wipe spills.
Scientific rationale
Several wavelengths reduce percentage uncertainty; fixed medium allows effect of frequency to be tested; wave speed depends on medium.