This experiment explores and analyzes the free resources available online that can be used in teaching and learning physics. The experiment consists of using the audio output from a computer to vary the frequency in one end of a string using SweepGen software, available free online. This paper presents two different methods for determining the velocity of wave propagation in the string and its dependence on the traction of the cord: analysis of video with high acquisition rate through the use of Tracker and a phototransistor connected directly to the microphone input of a PC. The results obtained are convergent indicating the effectiveness of the methods developed and extremely low cost to allow performing experiments on wave and an understanding of the phenomenon of resonance, so present in our daily life.
stationary waves; resonance; new technologies in education; acquisition of data
