An open–open organ pipe produces a note of frequency 660 Hz in its third harmonic. The speed of sound in air is 330 m s−1.
(a) Calculate the length of the pipe.
(b) If the same pipe is now closed at one end without changing its length, determine whether it can still produce a 660 Hz note. Give suitable calculations to justify your answer and, if possible, identify the harmonic number for which the note would occur.