A KUNDT'S TUBE TO OBTAIN THE SPEED OF SOUND AT DIFFERENT TEMPERATURES

Abstract

In this work we describe how we designed and built an acoustic system that allowed us to adapt a Kundt’s
tube for the measurement of the speed of sound at different temperatures. The air column inside the tube
was excited by a speaker at a frequency of 2 kHz. We changed the air column length by moving a piston
throughout the tube, and we measured and recorded that length when we observed a resonance signal
on the oscilloscope screen. This procedure was repeated at different temperatures, ranging from 19^○C to
115^○C. Then it was calculated the propagation of the speed of sound based on the temperature. The results
were compared with those predicted by the classical model, which assumes that air is an ideal diatomic gas,
and that the acoustic phenomenon is an adiabatic process. Finally, it was found a satisfactory agreement
between the experimental values and those predicted by the classical model.