In the figure below, S is a small loudspeaker driven by an audio oscillator with a frequency that is varied from 1000 Hz to 2000 Hz, and D is a cylindrical pipe with two open ends and a length of 55.0 cm. The speed of sound in the air-filled pipe is 344 m/s.

Question

(In the figure s is a little speaker next to the pipe D)

(a) At how many frequencies does the sound from the loudspeaker set up resonance in the pipe?
? frequencies
(b) What is the lowest frequency at which resonance occurs?
? Hz
(c) What is the second lowest frequency at which resonance occurs?
? Hz

Answer 1

Isn't the pipe length equal to 1/2 wavelenght?

n*freq(2*length)=speedsound
The lowest frequency will be n=1
the second lowest will be n=2

Answer 2

Ignore this post. My mind is tired.