The air column in a pipe closed at one end is made to vibrate in its second overtone by a tuning fork of frequency 440 Hz. The speed of sound in air is 330 m s−1. End corrections may be neglected. Let P0 denote the mean pressure at any point in the pipe, and ΔP0 the maximum amplitude of pressure variation.
(1) Find the length L of the air column.
(2) What is the amplitude of pressure variation at the middle of the column?
(3) What are the maximum and minimum pressures at the open end of the pipe?
(4) What are the maximum and minimum pressures at the closed end of the pipe?