We experimentally demonstrate an avoided crossing in an acoustic system, consisting of two coupled PVC tube sections. One section has a fixed length, while the other has a variable length. Coupling between these tube sections is controlled by an aluminum diaphragm with a variable hole size. The avoided crossings in the acoustic system are compared to those of a quantum infinite square well split into two regions—one of fixed length and another of variable length. The two regions are separated by a delta potential well that controls the coupling between the two regions. We demonstrate that the acoustic and quantum systems exhibit similar avoided crossing behaviors.

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