About Meter Coffee
What happens
- Real sizes: a brass tumbler 6.5 cm tall and a davara 8.5 cm across.
- The coffee stays level as you tilt. It pours once the level reaches the lip, and faster the higher it rises (weir flow).
- The stream falls at 9.8 m/s² and gets thinner as it speeds up. The faster it lands, the more air it traps, so a higher pour makes more froth.
What you hear
- The splash, plus bubbles ringing at their own pitch: smaller bubbles sing higher.
- Dry brass rings like a small bell until coffee covers the bottom.
- The air above the coffee rises in pitch as the vessel fills.
The Chennai bit
- “Meter” coffee is poured from arm’s length to cool it and froth it. The davara (the wide bowl) catches what you miss.
Inspired by A coffee counter in Triplicane, Chennai, India.