Is Watching a Kettle Actually Making It Boil Faster?

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In summary, an experiment was done in which people timed how long it took water to boil, if it was watched or not watched. The results showed that watched water boiled faster than un-watched water. However, this is only true at normal temperatures. If the "watched" pot doesn't have a lid on it (so you can watch it), then the "watched" pot will take longer to boil. This was done in the classical limit, which means that once you observe, the experiment is altered and the results no longer hold.
  • #1
Bigtex005
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I read of an experiment in which people actually timed how long it took water to boil, if it was watched and not watched. The results were that indeed watched water boiled faster. Now at first this blew my mind because I can't believe no one had tried it before, or maybe they have it was just the first time the people in the article had done it, who knows. Anyway, if this is true, are quantum effects at work here, or is this post just stupid? Please be kind if the latter is the case. :smile:
 
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  • #2
Are there any other reasons that caused the different length of time? I can't believe the result unless it is rigorously and repeatly tested.
 
  • #3
I agree, if it is repeated many times, THEN it is believable
 
  • #4
where did you read about this? I assume it wasn't a scientific journal...
 
  • #5
Hello Bigtex005,

I only know the phrase "a watched pot never boils" in connection with the "Quantum Zeno Effect".
http://www.lassp.cornell.edu/ardlouis/dissipative/Quantum_Zeno.html

But this doesn't have to do with water, it is about "freezing" a quantum state by measuring the quantum system again and again.
http://www.physics.uiuc.edu/People/Faculty/profiles/Kwiat/Interaction-Free-Measurements.htm#Zeno
 
  • #6
This depends on temperature. At normal temperatures reached by a household kettle, neither a watched nor unwatched kettle boils.
 
  • #7
Of course, if the "watched" pot doesn't have a lid on it (so you can watch it) and the "unwatched" pot does, then of course, the "watched" pot will take longer!
 
  • #8
HallsofIvy said:
Of course, if the "watched" pot doesn't have a lid on it (so you can watch it) and the "unwatched" pot does, then of course, the "watched" pot will take longer!

Hehe, I was about to post the same observation :approve:

cheers,
Patrick.
 
  • #9
Bigtex005 said:
I read of an experiment in which people actually timed how long it took water to boil, if it was watched and not watched. The results were that indeed watched water boiled faster. Now at first this blew my mind because I can't believe no one had tried it before, or maybe they have it was just the first time the people in the article had done it, who knows. Anyway, if this is true, are quantum effects at work here, or is this post just stupid? Please be kind if the latter is the case. :smile:

I think you're missing the point here.

An unwatched pot cannot have its boiling vs. not boiling time determined - the pot is unobserved. That means unobserved, unlistened to, un-everything-that-tells-you-what-it's-doing. And that includes listening for the whistle. There is no such thing as "passive" observation. If there is some form of information transfer (heat, light, sound) that is exiting the pot, such that we might see/hear/feel it and thus determine what it is doing, then the boiling/not boiling state collapses.


As with quantum mechanics, as soon as you observe, you alter the experiment.
 
  • #10
DaveC426913 said:
I think you're missing the point here.

An unwatched pot cannot have its boiling vs. not boiling time determined - the pot is unobserved. That means unobserved, unlistened to, un-everything-that-tells-you-what-it's-doing. And that includes listening for the whistle. There is no such thing as "passive" observation. If there is some form of information transfer (heat, light, sound) that is exiting the pot, such that we might see/hear/feel it and thus determine what it is doing, then the boiling/not boiling state collapses.


As with quantum mechanics, as soon as you observe, you alter the experiment.

You need to be careful in using that phrase because in the classical limit, you do not "alter" an experiment upon observation. And unless I missed something, what has been described is not a quantum mechanics experiment. If it is this easy to observe quantum effects, QM would not be this mysterious.

We also need to keep in mind that when question like this, and at this LEVEL, is being asked, the word "observation" has a rather pedestrian meaning. Most people associate it with 'seeing' with their own eyes. I suggest that the OP here is indicating an observation by the participants in actively looking and waiting for the water to boil, and considers doing this automatically or remotely without anyone looking as something different. Unless he/she explains further, we'll never know exactly if this is true.

[Note: people who say "I read somewhere..." or "I heard somewhere..." should REALLY put some effort into giving an exact citation on the source. If you can't, there's no way for us to double check if what you read is right, or if you simply misinterpret what was said!]

It is imperative that we present our answers within the frame of understanding of the person who pose the question. We have seen how quacks can really run with things because they read about things that have specific meaning with the context of physics, but with their lack of understanding, have completely different picture to them.

Zz.
 
  • #11
Ok, I cannot give reference to this experiment, I tried to find it again but couldn't. It was found just by surfing around. Next time I post I will give references. 2 things though, first I typed the result of that experiment incorrectly, the watched pot boiled slower not faster. Second thing is that the experiment said they basically just set the water up to boil, and then tried a couple of different things, left the kitchen, stayed in the kitchen but turned around, etc... The results were something like 20 seconds difference between the boiling time of a watched and unwatched kettle. Anyway, thanks for being kind when answering my stupid post :smile: By the way, I am pretty sure that this experiment wasn't in a scientific journal. I think it was some college student's class website or something to that effect. Better questions to come I promise, thanks for the replies.
 
  • #12
Dave brings up a point I was going to speak to. The time at which the kettle boils is merely a recorded time at which the observer became aware it was boiling. If you watch a kettle, you know the instant it begins boiling. If you check it every two minutes, you might write down a time that's up to two minutes later than boiling actually began or, if your observation is very "lucky", you might record time that is spot-on. You will not, however, record a time that is two minutes early (to compensate for the ones that were two minutes late), and so your observations will statistically tend toward later boiling times.
 
  • #13
ZapperZ said:
... unless I missed something, what has been described is not a quantum mechanics experiment...

...We also need to keep in mind that when question like this, and at this LEVEL, is being asked, the word "observation" has a rather pedestrian meaning. ...

...It is imperative that we present our answers within the frame of understanding of the person who pose the question.
Zz.
No, "..in the frame of where it was asked..."

It was posted in the Quantum Physics forum. The poster is looking for an answer of the thought experiment type, framed in quantum physics logic (a la Schrodinger's Cat).
 
  • #14
DaveC426913 said:
No, "..in the frame of where it was asked..."

It was posted in the Quantum Physics forum. The poster is looking for an answer of the thought experiment type, framed in quantum physics logic (a la Schrodinger's Cat).

But do you think you have left a reasonably accurate description of this apparent "water boiling at different rates" thing by ending it with "As with quantum mechanics, as soon as you observe, you alter the experiment."? If I am ignorant of what QM is, I would jump to the conclusion that classical, macroscopic events such as boiling rate of water is depending on whether I physically look at it or not, or if I measure it. This would violate all classical mechanics EVEN in its realm of validity, because you have removed one of its basic tenets where the "observer" plays no role.

If this is what you are implying, then we need to first and foremost establish that water boiling in a kettle is a quantum event and show that it cannot be described accurately with classical thermodynamics.

Zz.
 
  • #15
Sounds like something from the JIR to me.
 

1. Why does a watched kettle seem to take longer to boil?

There are a few possible reasons for this phenomenon. One reason is that when we are actively watching something, time seems to pass more slowly. Another reason is that when we are waiting for something to happen, we tend to pay more attention to it, making it feel like it is taking longer.

2. Is there any scientific evidence to support the saying "a watched kettle doesn't boil"?

While there is no specific research on this specific saying, studies have shown that our perception of time can be influenced by our attention and expectations. So in a sense, there is some scientific basis for the saying.

3. Does the material of the kettle affect how long it takes to boil?

Yes, the material of the kettle can affect how quickly it heats up and boils. For example, a copper kettle will heat up faster than a glass one because copper is a better conductor of heat.

4. Is there a way to make a watched kettle boil faster?

Unfortunately, there is no known way to make a watched kettle boil faster. However, you can try distracting yourself with another task or simply walk away and come back when the water is boiling.

5. Does the amount of water in the kettle affect how long it takes to boil?

Yes, the more water you have in the kettle, the longer it will take to boil. This is because it takes more energy to heat a larger volume of water. So if you want your kettle to boil faster, only fill it with the amount of water you need.

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