Week 5
Vibration of a string fixed at both ends. The white line in this animation is at the wrong location with respect to the violin (the left end should be at the bridge, the right end at the end of the fingerboard that is not shown) and the amplitude of the vibration is larger than normal for a violin string. It is of course understood that the vibration is shown in slow motion.
You can add or eliminate various harmonics by checking or unchecking the boxes. They are shown in slow motion but in correct relationship to the fundamental. There is apparently no control over the phases or the amplitudes of the harmonics. Nevertheless you can appreciate the complexity of vibration produced by superimposing just a few harmonics. Checking only the 4th and 5th harmonic gives you a wavetrain about half the size of the string that clearly reflects successively from one, then the other, end.
Longitudinal standing waves shown both via the actual motion of the medium (which is hard to show except by such animation) and in the transverse representation. You can choose various boundary conditions (open or closed ends) and various harmonics. The wavelength and frequency calculator will check your calculations based on table 3-7 of our text.