Most People Don’t Know Wine Moves Like This | EVERYDAY MYSTERY

TL;DR

Wine tears, or legs, on a wine glass are caused by the Marangoni effect, a surface tension gradient created by the evaporation of alcohol, which can indicate the alcohol content but not the quality of the wine.

Transcript

• [Dianna] I think that that's kind of the most amazing thing to me, is this, the little bounce of the droplet. And you don't usually notice that when you watch wine and it tears.
• [Paula] You don't, 'cause you think it's just-
• That's so cool. Oh my gosh. Hey, I'm Dianna and I'm having a bad hair day. So there's this really cool thing that wine ... Read More

Key Insights

• 😂 Wine tears, or legs, are caused by the Marangoni effect, which is the movement of fluid due to a surface tension gradient.
• 🍷 The evaporation of alcohol in wine creates a surface tension gradient, causing the fluid to move up the glass walls and form tears.
• 🍷 Wine tears only indicate the alcohol content of the wine and not its quality.
• 👷 The Marangoni effect has applications in other fields, such as thermal management systems and TIG welding for spacecraft construction.
• ❓ The Marangoni effect is responsible for the movement of molten steel in welding and the distribution of fluid in various systems.
• 🫗 The Marangoni effect can be observed in other liquids with a difference in surface tension, such as whiskey.
• 👨‍🔬 The Marangoni effect is a fascinating area of research in applied mathematics and has practical implications in various industries.

Questions & Answers

Q: What is the Marangoni effect and how does it relate to wine tears?

The Marangoni effect is the movement of fluid due to a surface tension gradient. In the case of wine tears, the evaporation of alcohol creates a surface tension gradient, causing the fluid to move up the glass walls and form tears.

Q: Do wine tears indicate the quality of the wine?

No, wine tears only indicate the alcohol content of the wine, not its quality. The stronger the alcohol content, the more pronounced the wine tears will be, but they do not provide any information about the taste or quality of the wine.

Q: Can the Marangoni effect be observed with other liquids?

Yes, the Marangoni effect can be observed with other liquids that have a difference in surface tension, such as whiskey. However, it does not occur with liquids like orange juice or grape juice, as they do not contain alcohol.

Q: How is the Marangoni effect used in other applications?

The Marangoni effect is used in various applications, such as thermal management systems and TIG welding for spacecraft construction. By manipulating the surface tension gradient, it helps with fluid flow and distribution.

Summary & Key Takeaways

• Wine tears form on a wine glass when the fluid is pushed up the walls of the glass due to a higher surface tension at the meniscus caused by the evaporation of alcohol.

• The movement of the tears is due to the Marangoni effect, a surface tension gradient created by the difference in surface tension between alcohol and water in the wine.

• The tears can last for a long time as the ridge at the top of the glass is constantly being replenished with fluid.