RESONANCE: ' The property whereby any vibratory system responds with
maximum amplitude to an applied force having the a frequency equal to its
In english, this means that any solid object that is struck with a sound
wave of equal sound wave vibrations will amplitude the given tone. This
would explain the reason why some singers are able to break wine glasses
with their voice. The vibrations build up enough to shatter the glass. This is
Resonance can be observed on a tube with one end open. Musical tones
can be produces by vibrating columns of air. When air is blown across the
top of the open end of a tube, a wave compression passes along the tube.
When it reaches the closed end, it is reflected. The molecules of reflected air
meet the molecules of oncoming air forming a node at the closed end. When
the air reaches the open end, the reflected compression wave becomes a
rarefaction. It bounces back through the tube to the closed end, where it is
reflected. the wave has now completed a single cycle. It has passed through
the tube four times making the closed tube, one fourth the length of a sound
wave. By a continuous sound frequency, standing waves are produced in the
tube. This creates a pure tone.
We can use this knowledge of one fourth wavelength to create our own
demonstration. It does not only have to be done using wind, but can also be
demonstrated using tuning forks. If the frequency of the tuning forks is
known, then v=f(wavelength) can find you the length of your air column.
Using a tuning fork of frequency 512 c/s, and the speed of sound is
332+0.6T m/s, temperature being, 22 degrees, substitute into the formula.