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Take an empty cup.
Put in a few ice cubes.
Top up to the brim with tap ater.
As the ice melts does water come out of the cup??
.... does it heck
So why are we being told that the oceans will rise in years to come?
Roy Kelly PhD ... ( prefers hot dinners )
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Surely its the ice above the water level that will cause the problems when and IF it melts?
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But ice cubes in the cup float...
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Roy, The answer in it`s simplest terms is, THERMAL EXPANSION. As water warms up it occupies more space.
Jim
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Sorry Jim but I can't grasp that. The ice in mycup heats up to room temp, but doesn't expand...
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quote:
Originally posted by ishake
Sorry Jim but I can't grasp that. The ice in mycup heats up to room temp, but doesn't expand...
Trying to recollect my O level General science, when the ice melts it occupies a lower volume than when it was in solid form. Ice has a density of 0.91g/cc whereas water is 1.0, which explains why ice floats on water. However the cause of sea levels rising is attributed not to the melting of the Polar ices, but the increase in global temperatures caused by the effects of Carbon emissions. Fill a pan to the brim with water and slowly heat it up, the water will flow over the top of the pan. Thermal expansion.
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Water has its highest density at 4 degrees C. As it cools below that, it starts to expand again, which is why ice causes burst pipes.
Melting ice caps will cause a rise in sea level because a lot of it is on land, not floating in the sea.
Frank
Frank Damp (wife Eileen, nee Nixon)
Leyland resident 1941-1965, emigrated to the US in 1968,
retired to Anacortes, Washington State, USA in 1999.
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Right, I stand corrected.
On a point of order does water need to be -3.5 before it will burst a pipe ?
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No, Roy, by the time it turns to ice, the damage is done. I don't remember off-hand what the expansion is between 4C and 0C, but its enough to break pipes once it turns to a solid.
Bear in mind that's the actual water temperature, not the air temp in the vicinity of the pipe. With ABS or PVC pipes, you may have a bit of leeway as the materials are much better insulators that copper or galvanised steel.
On another subject, Roy, we get a lot of stories about Jimi Hendrix in this area since he was a Seattle native. The family is into a big argument over his legacy and several properties he bought. The cases show up on the news quite frequently. Not being into that kind of music, I always thought he was an exhibitionist rather than a musician. Just my personal opinion. I didn't like Curt Cobain either!
Frank
Frank Damp (wife Eileen, nee Nixon)
Leyland resident 1941-1965, emigrated to the US in 1968,
retired to Anacortes, Washington State, USA in 1999.
