The Materials used for these small demos are all relatively easy to find. Firstly, a simple pendulum was made with a beaker stand and a metal bar suspended horizontally. Weight were hung from places on the pole at equal distance from eachother.
Tuning forks can be found in physics labs, or from music stores. They vary in size, as the larger ones produce louder pitch and therefore, more audible results.
Any guitar will do, although electric guitars through amps make much louder noises for the demonstration. If a microphone is available, the program at _______ can be downloaded and used to identify frequencies while using the tuning forks and the guitar.
Any solid metal bar that can be comfortably held between two fingers works well. Again, the program can be used to identify the exact pitch and tone of the bars resonant frequency. The Ebow is the one tricky thing to get. They are expensive to buy, and it is much more practical to borrow one from a guitar player. Not everybody has them, but they are very interesting to look at and use when discussing resonance.
Other items, such as a wine glass or a sea shell, are interesting items when demonstrating resonance. By rubbing the wine glass around the rim, you can excite the resonant pitches. Random inaudible sound waves are always in the air in a room, and if any of them happen to match or come close to the resonant frequency of a seashell structure, then there will be an audible noise from inside the seashell. Hence, the 'sound of the sea' is heard.
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