Tea in Milk: Reasons for Floating Upwards

  • Context: High School 
  • Thread starter Thread starter springBreeze
  • Start date Start date
Click For Summary
SUMMARY

The phenomenon of cold milk initially sinking and then floating upwards in tea is primarily due to the circulatory system established when the milk is poured into the tea. While the density of milk is slightly higher than that of water, the mixing and convective-inertial flow caused by pouring creates a dynamic that allows the milk to rise. This behavior is observable in other liquids with similar density and viscosity characteristics, making milk's behavior in tea a clear example of fluid dynamics in action.

PREREQUISITES
  • Understanding of fluid dynamics principles
  • Knowledge of density and viscosity concepts
  • Familiarity with miscibility of liquids
  • Basic principles of thermal dynamics
NEXT STEPS
  • Research fluid dynamics and convection currents
  • Explore the properties of density and viscosity in liquids
  • Study the miscibility of different liquid combinations
  • Investigate thermal dynamics and temperature effects on liquid behavior
USEFUL FOR

Students and professionals in physics, chemistry, and culinary arts, as well as anyone interested in the science behind everyday phenomena like mixing liquids.

springBreeze
Messages
9
Reaction score
0
While my friend was making a nice cup of British tea today, I noticed that when he put cold milk into the tea, it first sank but then almost immediately afterwards floated upwards. He thought it could be that the cold milk warmed up and hence floated to the top since warmer liquids are less dense. Is that the only reason or are there others?
 
Physics news on Phys.org
He added milk to tea ... shakes head ...
 
springBreeze said:
He thought it could be that the cold milk warmed up and hence floated to the top since warmer liquids are less dense.
Well, the milk didn't get warmer than the tea it was sitting in, now did it?

1] Fat floats in water.
2] Pouring a liquid into another liquids will tend to set up a circulatory system. bringing the milk back up top.
 
I am with Dave's 2 - I would bet mainly on circulation. Milk density is slightly higher than that of water, but not enough to stay on the bottom. Most likely any other liquid with density and viscosity similar to that of water will behave exactly the same way, milk is just easier to see.
 
mgb_phys said:
He added milk to tea ... shakes head ...

You have milk without tea:confused: Why?
 
mgb_phys said:
He added milk to tea ... shakes head ...

Echo that.
 
madmike159 said:
You have milk without tea:confused: Why?

Woops I ment tea without milk lol. disgusting
 
springBreeze said:
While my friend was making a nice cup of British tea today, I noticed that when he put cold milk into the tea, it first sank but then almost immediately afterwards floated upwards. He thought it could be that the cold milk warmed up and hence floated to the top since warmer liquids are less dense. Is that the only reason or are there others?

I'm sure part of the answer is becasue he *poured* it in, rather than floated it on (i.e. black and tans, pousse-cafe drinks, etc.). Then, because milk and tea are miscible, mixing ocurred along with whater convective-inertial flow ocurred.
 
Milk with Tea FOR THE WIN
 
  • #10
NoobixCube said:
Milk with Tea FOR THE WIN

Hell yea, were going of topic though.
 

Similar threads

High School Why did my coffee foam over when I added milk?
  • · Replies 13 ·
Replies
13
Views
8K
High School Colder bedrooms when outside is warmer
  • · Replies 34 ·
2
Replies
34
Views
3K
Undergrad Calculating Sugar Poured in Tea: A Fun High School Math Problem
  • · Replies 1 ·
Replies
1
Views
2K
High School Simple liquid/gas law question and liquid transfer query
  • · Replies 9 ·
Replies
9
Views
2K
Graduate Focus all of your ire on me, if you would
  • · Replies 4 ·
Replies
4
Views
3K
The Scientist as Hero - or not
  • · Replies 1 ·
Replies
1
Views
3K
Do Gasoline Pumping Tips Really Help You Save Money?
  • · Replies 22 ·
Replies
22
Views
7K
Cooking (Thermodynamics) Problems
  • · Replies 14 ·
Replies
14
Views
4K
Plate Tectonics: The Asthenosphere and Lithosphere
  • · Replies 33 ·
2
Replies
33
Views
19K
What are your thoughts on 'Ad Astra' and Will Smith's upcoming Gemini Man?
  • · Replies 12 ·
Replies
12
Views
4K