In the experiment, the wine glass is excited by means of a frequency generator to vibrate. The frequency of the generated sound waves coincides with the natural frequency of the wine glass. The sound pressure stimulates the glass to vibrate, so that it comes to the so-called resonance, the forced swinging of the system.
The energy transfer is maximum, the glass vibrates more and more until finally the load limit is exceeded and this shatters. The resonance catastrophe has occurred. In general, every oscillatory system has a so-called natural frequency. For example, if you hit a wine glass with a spoon, it vibrates with just this natural frequency, so it performs a specific number of oscillations in a certain time interval. In this experiment, it has been able to reinforce these.
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