The Naked Scientists
  • Login
  • Register
  • Podcasts
      • The Naked Scientists
      • eLife
      • Naked Genetics
      • Naked Astronomy
      • In short
      • Naked Neuroscience
      • Ask! The Naked Scientists
      • Question of the Week
      • Archive
      • Video
      • SUBSCRIBE to our Podcasts
  • Articles
      • Science News
      • Features
      • Interviews
      • Answers to Science Questions
  • Get Naked
      • Donate
      • Do an Experiment
      • Science Forum
      • Ask a Question
  • About
      • Meet the team
      • Our Sponsors
      • Site Map
      • Contact us

User menu

  • Login
  • Register
  • Home
  • Help
  • Search
  • Tags
  • Recent Topics
  • Login
  • Register
  1. Naked Science Forum
  2. On the Lighter Side
  3. New Theories
  4. How does freezing water break a pipe?
« previous next »
  • Print
Pages: [1]   Go Down

How does freezing water break a pipe?

  • 6 Replies
  • 9451 Views
  • 0 Tags

0 Members and 1 Guest are viewing this topic.

Offline JukriS (OP)

  • Sr. Member
  • ****
  • 115
  • Activity:
    0%
How does freezing water break a pipe?
« on: 31/10/2008 11:12:46 »
"How can freezing water expand, even bursting metal pipes, with no energy input to explain it?

A: According to today's science, this is impossible. Every output of energy requires a balancing energy input in order
to remain within our laws of physics. A balloon left in the sun will expand and burst, in the process doing work against the
surrounding atmosphere and its elastic skin, which is balanced by the energy input from the sun, so it is no mystery. However,
freezing water has no energy input -- in fact, just the opposite. Energy continually drains from the water as it cools toward
freezing. So, how does the water suddenly expand with such force from within that it easily bursts metal pipes? No solid
answers to this mystery can be found from today's scientists -- only confused hand-waving diversionary responses that still
do not answer this clear energy balance violation."

http://www.thefinaltheory.com/scienceflaws.html

Is today's physics hand waving physics?

Thats the way it is!

« Last Edit: 01/11/2008 10:25:31 by chris »
Logged
 



Offline graham.d

  • Naked Science Forum King!
  • ******
  • 2207
  • Activity:
    0%
  • Thanked: 1 times
Re: How does freezing water break a pipe?
« Reply #1 on: 31/10/2008 13:32:36 »
I believe the reason that water expands close to feezing is to do with changing from a compact state, with little wasted space between the aligned hydrogen bonded water molecules at about 4C, to a crystalline state which requires the bonds to be deformed slightly, and occupying more space as a result, at 0C. I don't think there is any violation of conservation of energy laws here. In fact holding the freezing water in a confined space whilst continuing to cool will delay the phase change to a lower temperature in the same way that applying pressure to ice close to 0C will cause it to melt. I think it is just that we are used to a correlation between expansion and increase in temperature. If you take a long piece of metal and cool it so it contracts, it would not surprise anyone to think that you could extract some energy from the movement of the end of the metal if the other end were fixed - to lift a small weight via a system of levers for example.
Logged
 

lyner

  • Guest
Re: How does freezing water break a pipe?
« Reply #2 on: 31/10/2008 19:14:35 »
Considering the energy involved, there is a lot of energy transferred whilst water is cooling and freezing. Some of it, and there is not a lot of actual energy involved, goes towards some mechanical work.
Why do I say there is not much mechanical work? Work is defined as force times distance. The force may be high but the distance is very little.
The actual thermal energy transferred is enormous in comparison.
If you really insist I will do the sums but I am tired.
Logged
 

Offline DoctorBeaver

  • Naked Science Forum GOD!
  • *******
  • 12653
  • Activity:
    0%
  • Thanked: 4 times
  • A stitch in time would have confused Einstein.
Re: How does freezing water break a pipe?
« Reply #3 on: 01/11/2008 05:09:22 »
I believe I'm right in saying that all other things being equal, temperature increases with pressure. If the water was cooled to freezing point in a rigid container that was strong enough not to split, it would try to expand but not be able to. That would increase the pressure and, hence, the temperature also. Could the water be stopped from freezing like that?
Logged
 

Offline graham.d

  • Naked Science Forum King!
  • ******
  • 2207
  • Activity:
    0%
  • Thanked: 1 times
Re: How does freezing water break a pipe?
« Reply #4 on: 01/11/2008 09:57:06 »
Dr B, your initial premise is that the water and container was being cooled so, by definition, the temperature will not increase. The pressure lowers the freezing point but will not prevent freezing if cold enough.
Logged
 



lyner

  • Guest
How freezing water can break pipe!
« Reply #5 on: 01/11/2008 10:36:34 »
Your rule of thumb relating temperature and pressure applies to gases, under adiabatic conditions (in an insulated container) because the work done to increase the pressure increases the internal energy. In an isothermal change , you increase the pressure slowly and the excess internal energy leaks away to the surroundings. What I am saying is that high pressure doesn't actually imply a higher temperature. Increasing pressure does, however, involve an input of energy. (Subtle difference)

Where you have a change of state (or even interaction between molecules) the simple model no longer applies. When water is frozen (near 0C), you can melt it by increasing the pressure (e.g. under ice skate blades). The energy you have added supplies the latent heat of melting.

The pressure due to freezing is not 'unstoppable' and you can delay freezing if you keep the water in a strong enough container. The temperature could not 'go up' because the surroundings would be taking energy away. What you could say, however, is that there would be less energy lost to the container if it were under pressure than if it were not - because the latent heat of freezing would not be available.

If you want to use the word "try", you are implying an intention and substances certainly don't have intentions. This may sound very nitpicking (not for the first time!) but that sort of word can lead one into problems. Using inverted commas ('try') shows that you mean "behaves as if it were trying to", which is a better way of putting it.
Logged
 

Offline DoctorBeaver

  • Naked Science Forum GOD!
  • *******
  • 12653
  • Activity:
    0%
  • Thanked: 4 times
  • A stitch in time would have confused Einstein.
How does freezing water break a pipe?
« Reply #6 on: 02/11/2008 20:22:29 »
graham & SC - thank you.
Logged
 



  • Print
Pages: [1]   Go Up
« previous next »
Tags:
 
There was an error while thanking
Thanking...
  • SMF 2.0.15 | SMF © 2017, Simple Machines
    Privacy Policy
    SMFAds for Free Forums
  • Naked Science Forum ©

Page created in 0.47 seconds with 39 queries.

  • Podcasts
  • Articles
  • Get Naked
  • About
  • Contact us
  • Advertise
  • Privacy Policy
  • Subscribe to newsletter
  • We love feedback

Follow us

cambridge_logo_footer.png

©The Naked Scientists® 2000–2017 | The Naked Scientists® and Naked Science® are registered trademarks created by Dr Chris Smith. Information presented on this website is the opinion of the individual contributors and does not reflect the general views of the administrators, editors, moderators, sponsors, Cambridge University or the public at large.