Oscillations and Waves > Waves > Interference and Diffraction DCS# 3B55.40

QUINCKE'S TUBE


APPARATUS
Quincke's tube 202-07-B
function generator 202-08-G
horn or lavalier microphone 202-07-C


DESCRIPTION
The right arm of the tube is like a trombone slide.  Its length can exceed that of the left arm by 0 to 30 cm.  An 1100 Hz note, C#5, has a wavelength of about 30 cm, so you hear a minimum with the slide halfway out, a maximum with it fully extended.  Even at the minimum you hear some sound since the note has some harmonic content and the even harmonics interfere constructively.
-REW