To study the behavior of a standing wave; to measure the wave velocity and to study some of the factors
which affect the wave velocity.
Mechanical Wave driver; string; rubber band; table clamps, pulley; weight set; weight hanger; meter stick;
double meter stick; caliper jaws; timer; c-clamp.
If one end of a string is attached to a vibrating body, and if a tension is present in the string, a periodic
waveform will be propagated along the string.
, T, of such a wave is the time for one complete
cycle of vibration of any particle of the string.
It is also the time required for one complete waveform to
pass a particle of the string.
The frequency, f, is the number of complete cycles of a particle of the string in
a unit time interval.
It is also the number of complete waveforms passing a particle of the string in a unit
The frequency is related to the period by f =
, A, is the maximum displacement of any particle, measured from its equilibrium position.
(lambda), is the distance between two successive particles of the string which are in
Particles in the same relative position on each of the waveforms are said to be in phase.
), c, is the velocity with which a waveform (or any particular phase of it) is
propagated along the string.
The amplitude, A, and the wavelength,
, may be best visualized by looking at a snapshot of a waveform.
Such a snapshot is illustrated in Figure 1.
The y coordinate is the displacement of a particle of the string.
If a particular particle on the string is observed and its displacement, as it oscillates up and down, is plotted
as a function of time t, a curve, as illustrated in Figure 2, results.