![PDF] The resonant excitation of a wineglass using positive feedback with optical sensing | Semantic Scholar PDF] The resonant excitation of a wineglass using positive feedback with optical sensing | Semantic Scholar](https://d3i71xaburhd42.cloudfront.net/1da3474a90da5d9ddca265804ae9745aa26570cf/8-Figure10-1.png)
PDF] The resonant excitation of a wineglass using positive feedback with optical sensing | Semantic Scholar
![Rubbing with a finger over a glass gives a resonance to the glass. The more water is in the glass the lower the produced sound Stock Photo - Alamy Rubbing with a finger over a glass gives a resonance to the glass. The more water is in the glass the lower the produced sound Stock Photo - Alamy](https://c8.alamy.com/comp/2J5R52X/rubbing-with-a-finger-over-a-glass-gives-a-resonance-to-the-glass-the-more-water-is-in-the-glass-the-lower-the-produced-sound-2J5R52X.jpg)
Rubbing with a finger over a glass gives a resonance to the glass. The more water is in the glass the lower the produced sound Stock Photo - Alamy
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