The discussion revolves around the acoustic properties of wine glasses, specifically focusing on why they exhibit four nodes in their fundamental mode of vibration, which corresponds to the 4th harmonic. Participants explore the relationship between the physical structure of the glass and its vibrational characteristics.
The conversation has progressed with some participants clarifying the original question about the nodes and discussing the mechanics of oscillation. There is an ongoing exploration of how the presence of water might affect the frequency, although no consensus has been reached on the specifics.
Some participants express a desire to focus the discussion on a single thread, indicating a potential complexity in the topic that may require further clarification.
If the glass has to move more water in the oscillation, it needs more time for the same displacement (at the same elongation => same force).and also does the fundamental frequency of the object (wine glass + water) change when water level is changed.