|Oscillations and Waves > Instruments > Air Columns||DCS# 3D30.10|
|rubber tubing with clamp||202-17-F|
|HP 200AB audio oscillator||202-08-G|
|2-liter beaker to fill tank||101-01-C|
|oscilloscope with camera||202|
Demonstrates both resonance and the
content of a distorted sine wave. Use f = 680 Hz, so wavelength
about 0.5 m. First put maximum generator output into scope, to show it
is distorted. Then connect scope to speaker, watch scope and
to sound as air column length increases from about 5 to 40 cm.
first fundamental resonance for about 12.5 cm, but it comes at 9 or 10
due to end correction. Next fundamental one is at about 35 cm,
between these two you hear and see others (higher in frequency) due to
the higher Fourier components, whenever the relationship
Add water just before demo is needed -- plexiglas tube leaks.