Date: Wed, 29 Nov 2006 21:12:24 GMT From: th <someguynospamwhere.se> Subject: Re: Terrible Screaming Noise
Greg Farris wrote: > In article <456DBBD4.90707nospamwhere.se>, someguynospamwhere.se says... > >> There is one other exception: Water expands when cooled below 4 degrees >> C. > > > This is true - though not the only known negative temperature expansion > coefficient. > > >> Due to this effect lakes freeze at the surface and we can go skating! > > > > Due to which effect? Wouldn't that be more closely related to the fact that > water becomes a solid at 0ƒC? > You are partly right, it's a combination of two effects: 1) if the solid wouldn't have expanded but become more dense than the water the ice would sink. 2) if the 0ƒC water would be the most dense it would also sink to the bottom of the lake and the entire lake water must reach 0ƒC before ice formation can start. Then just very shallow lakes would freeze during winter. -- th
