Assume the speed of sound in air is 373 m/s. This question again refers to a Quncke tube (as in question 2). Suppose the length of the longer tube is at the minimum length so there is total destructive interference when the frequency of the note played by the speaker at frequency f = 20 Hz. Now, the frequency of the sound increases at a steady rate: = 4.79 Hz/s. If the shorter dt tube remains at constant length, at what rate must the longer tube have to change in length, in cm/s, so you continuously have total destructive interference when f = 156 Hz? (The sign will tell if it is increasing or decreasing.)

Assume the speed of sound in air is 373 m/s. This question again refers to a Quncke tube (as in question 2). Suppose the length of the longer tube is at the minimum length so there is total destructive interference when the frequency of the note played by the speaker at frequency f = 20 Hz. Now, the frequency of the sound increases at a steady rate: = 4.79 Hz/s. If the shorter dt tube remains at constant length, at what rate must the longer tube have to change in length, in cm/s, so you continuously have total destructive interference when f = 156 Hz? (The sign will tell if it is increasing or decreasing.)