If I had two cups of hot water and put one in the fridge and left one

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Discussion Overview

The discussion revolves around a thought experiment involving two cups of hot water, one placed in a fridge and the other left on a table, to determine which would be cooler after 10 minutes. Participants explore the principles of cooling, common sense reasoning, and related phenomena such as the Mpemba effect.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants suggest that the rate of cooling depends on the temperature difference between the water and its surroundings, indicating that the fridge would likely be more effective unless the kitchen is very cold.
  • Others express skepticism about the need for physics to answer the question, implying that common sense should suffice.
  • A participant questions whether the inquiry is truly about cooling or if it relates to the Mpemba effect, which suggests that hot water can freeze faster than cold water under certain conditions.
  • Some participants note that the experiment is straightforward and could be easily conducted to find the answer.
  • There is a suggestion that various parameters beyond just room temperature must be considered when discussing the cooling rates.

Areas of Agreement / Disagreement

Participants express differing views on the necessity of physics in answering the initial question, with some emphasizing common sense while others focus on scientific principles. The discussion about the Mpemba effect introduces additional complexity, and no consensus is reached regarding the cooling rates or the implications of the experiment.

Contextual Notes

Participants mention that multiple factors, such as the temperature of the surroundings and other environmental conditions, influence the cooling process, indicating that the question may not have a straightforward answer.

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If I had two cups of hot water and put one in the fridge and left one on the table which one after 10 minutes would be cooler ?
I have no idea and have been asked this question, thanks in advance for the answer.
 
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All else being equal the rate of cooling depend son the temperature difference between the water and it's surroundings - so unless it's very cold in your kitchen, the fridge would be better.
 


Scully said:
If I had two cups of hot water and put one in the fridge and left one on the table which one after 10 minutes would be cooler ?
I have no idea and have been asked this question, thanks in advance for the answer.

Do you really need physics to answer this question? I mean, really? I don't want to be harsh, but common sense should tell you the answer.
 


Isn't physics simply asking 'why' to commonsense questions?

edit: I did think they would follow up with a more 'but why' type question !
 


Scully said:
If I had two cups of hot water and put one in the fridge and left one on the table which one after 10 minutes would be cooler ?
I have no idea and have been asked this question, thanks in advance for the answer.

Yeah I find very strange that you have no idea about the answer. Also, the experiment is quite easy to do (you only 2 glasses of water + a fridge).
Then putting the same finger in each glass should tell you the answer.
 


The real question is why is it that hot water will make ice-cubes faster than cold water...
 


James Leighe said:
The real question is why is it that hot water will make ice-cubes faster than cold water...
Oh... then it's a totally different question!
It has been discussed in this forum and I'm pretty sure more than once.
Read http://en.wikipedia.org/wiki/Mpemba_effect.
 


James Leighe said:
The real question is why is it that hot water will make ice-cubes faster than cold water...

It won't.

Except in very carefully-controlled circumstances.
 


mgb_phys said:
All else being equal the rate of cooling depend son the temperature difference between the water and it's surroundings - so unless it's very cold in your kitchen, the fridge would be better.

ok if the room was 20°C warmer what would the answer be ?
 
  • #10


Scully said:
ok if the room was 20°C warmer what would the answer be ?

You definitely didn't read the link I provided... There are many more parameters than the room temperature to take into account.
 

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