PhysicsLAB: Test Scenario: Experimental Speed of Sound

This scenario is based on the APB 1995 Form B FRQ #6.

Refer to the following information for the next four questions.

A hollow tube of length l = 52 cm, open at both ends as shown below, is held in midair. A tuning fork with a frequency f = 329 Hz vibrates at one end of the tube and causes the air in the tube to vibrate at its fundamental frequency.

(a) After sketching the waveform of the sound wave in the tube, determine its wavelength.

(b) Determine the speed of sound in the air inside the tube.

(d) Determine the frequency of the next harmonic at which this same air column could resonate.

Refer to the following information for the next two questions.

The tube is then submerged in a large, graduated cylinder filled with water. The tube is slowly raised out of the water and the same tuning fork, vibrating with frequency 329 Hz, is once again held a fixed distance from the top of the tube.

(e) Determine the height h of the tube above the water when the air column resonates for the first time.

(f) Determine the frequency of the next harmonic at which this same air column could resonate.