Project Title : Investigation of the effect of frequency on the resonance effect of sound in an open pipe
Project Type: Test a hypothesis: Hypothesis-driven research
This project aims to find out which are the frequencies that resonance occurs in an open pipe of 1m. Resonance is an effect where a wave is reinforced by reflection from a surface or synchronisation from a nearby object. When waves reinforce, they produce a stronger wave. We used a setup consisting of 50w speakers at both ends of an 1m acrylic tube, and inputted frequencies for the speakers to play. We then used a decibel meter to measure the sound intensity in the acrylic tube. Using the decibel meter, we then recorded the data down in a table and then plotted a graph for each decibel measured and the frequency that it was measured at (frequency against decibel). We found that at certain frequencies, the decibel measured is higher, peaking out with one frequency being the highest among these frequencies. That peaking frequency in each set is our resonant frequencies. However, another set of frequencies was significantly higher. This was the anormaly. On average, the frequencies during resonant frequencies were measured to be 5 dB more, while this frequency was higher by 10 dB, we concluded that this is due to the resonant frequency of the tube itself , the original resonance is combined with the resonance of the tube, increasing the strength much more. Using this information , we can increase the wave strength in this such as microwaves using resonance while using the same or even less amount of power. We also can reduce the amount of resonance in this that we do not want to vibrate intensely such as bridges and car bumpers. the resonance effect can also be applied to music, where at certain frequencies, the musician can use the same or even less energy to play, but still produce a loud sound.