When you pluck a stretched cord or string, you cause the whole length of the string to vibrate, producing a musical note. The frequency of this note depends upon three properties of the string: its length, its thickness (defined as mass per unit length) and its tautness (defined as tension).
To produce a higher note you can shorten the string, use a thinner string, or increase its tension. In the AcademyΓÇÖs laboratory experiment you can adjust the length of the string, or hang different weights from it to vary the tension. Then you can hear the different notes you have made.
The relationship between the different properties of the string and the note produced is always the same. It is defined by the mathematical formula displayed on our experiment -
(f is the frequency of the note produced, l is the length of the string, T is the tension and m the mass per unit length of the string).
In music, the higher note of an octave has exactly double the vibrating frequency
of the lower note. All the notes of the standard musical scale approximate to similar mathematical relationships. You can observe and study some of them as you play with our string experiment.
