A quadrangular rubber rope is inserted through the demonstration motor and a linear polarised fixed wave is generated. With the help of a stroboscope, the frequency and the wave length are determined. Then the phase velocity of ropewaves with a fixed tensile stress is ascertained. Subsequently, the mathematical relationship between the phase velocity of the rope and the tensile on the rope is examined.
Benefits
Difficult physics of phase velocity presented in a simple way
High-precision results thanks to use of special rope and stroboscope
Large and easy to see wave crests and troughs
Tasks
With constant tensile stress, the frequency f, which depends on the wavelength λ of the wave that propagates itself along the rope. The frequency is plotted as a function of 1/λ. From this graph, the phase velocity c is determined.
The phase velocity c of the rope waves, which depends on the tensile stress on the rope is to be measured. The quadrant of the phase velocity is plotted as a function of tensile stress.