Naked Science Forum

General Science => General Science => Topic started by: neilep on 19/01/2008 16:44:07

Title: Creaking Ice Cubes !!
Post by: neilep on 19/01/2008 16:44:07

Dearest Science Peeps ,

See these Ice Cubes ?

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brrrrrrrrr !!..cold eh ?...but they do look like quality ice cubes !!


What is the creaking sound that is caused when I am slowly crushing an ice cube with my teeth ?.....sounds like a creaking door...but very slowly !!


Try it !...you'll hear the same !!...probably not recommended if you have very sensitive teeth !!

So, what's it all about ?

Title: Creaking Ice Cubes !!
Post by: opus on 19/01/2008 22:41:10

... ice particles scraping past each other as you crush them with your teeth ...... perhaps...

Title: Creaking Ice Cubes !!
Post by: neilep on 20/01/2008 14:37:16

Quote from: opus on 19/01/2008 22:41:10

... ice particles scraping past each other as you crush them with your teeth ...... perhaps...

Thank You OPUS....sounds reasonable enough to me...............Certainly the pressure is paramount here......lets hope a passing Creaking-Ice-Cubeologist comments here too...

Title: Creaking Ice Cubes !!
Post by: chris on 20/01/2008 16:15:29

I might be wrong here, but squeezing ice makes it hotter - this is how ice-skates work - the pressure beneath the blade melts the ice slightly, lubricating the path of the blade across the ice.

So, the intense pressure at the point of contact between tooth and ice could warm up the ice making it expand and melt at that point and as it does so it resonates, hence the noise.

Does anyone agree with that?

Chris

Title: Creaking Ice Cubes !!
Post by: JimBob on 20/01/2008 19:57:43

I believe that the sound is due to mechanical action. It can either be the cracking of the ice itself or the mechanical grinding of your teeth against the ice.

Title: Creaking Ice Cubes !!
Post by: daveshorts on 23/01/2008 12:58:00

Quote from: chris on 20/01/2008 16:15:29

I might be wrong here, but squeezing ice makes it hotter - this is how ice-skates work - the pressure beneath the blade melts the ice slightly, lubricating the path of the blade across the ice.

Pressure will melt ice because water contracts when it melts applying pressure will favour liquid water over ice, but this will mean that the latent heat of melting will have to come from somewhere and it will cool the system down.

Although it has been said that ice skates are slippery because they melt the ice, I think it is now considered that the process is actually a lot more complex than this.

Title: Creaking Ice Cubes !!
Post by: JimBob on 23/01/2008 22:32:54

and then there is surface tension, effects of the confining and non-confining pressure involved ... a whole new discussion.

The most important event, I believe, is the mechanical fracturing of the ice. 

Title: Creaking Ice Cubes !!
Post by: neilep on 23/01/2008 22:43:14

THANK YOU THANK YOU ALL!!

Is it related to the creaking sound that glaciers make !!?...you know !!..stick a microphone in there and you get creaks !!