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How long would it take for your body to warm the entire tub of water?
With water or air at 23oC your body temperature is at least 13oC higher, so either in water or air you’re going to loose heat to the fluid surrounding you, (air is a fluid).The thermal conductivity of water is over twenty times greater than air, so if all other variables are equal then in water you’re going to lose heat much faster to your surroundings than in air.The movement* of the fluid surrounding you would affect the rate of heat loss: moving through the water when swimming will result in faster heat loss than if the colder fluid surrounding you was still.If you’ve ever fallen asleep in a bath which has gone cold you may have experienced this phenomenon: when you wake up the bathwater doesn’t feel too cold but gets much colder immediately when you move. The comparatively still water next to your skin has been warmed up by your body. Disturbing the water by moving brings colder water in contact with your skin and results in more rapid heat loss.[* cf wind chill]
Thanks Karen! Make it Guinness if you don't mind.
Rats! I thought you were serious.BTW, what stroke is Neil doing there? It can't be the doggie paddle. Maybe it's the sheepy paddle?
Dearest Klevur Peeps Whom Are Authorities On the Stuff They Know ,As a sheepy I of course luff to swim.....out of all the immersing my body in water and splashing about activities that there are..swimming is my all time fave.look, here I am enjoying some swimming fun ![attachment=9667]Me Swimming Yesterday.Don't be fooled, ewe know how the light can fool ewe in water ..that's bona fide me alright !Now that water was a very nice 23 degrees. .....thing is...so was the air temperature. So, when I got out of the pool and had dried myself off I felt considerably warmer than when I was in the water of the exact same temperature.Why's that then....despite the temperatures being exactly the same ...why did I feel colder in the water ?I so wish I knew !...I plan to have a pool party and I need to be ready to answer this kweschun should any of my sheepy pals ask it !..and they are a curious bunch..I am sure when they notice that the pool and air temp are the same that they will be queuing up expecting explanations !Hugs et shmsihesmwah mwah mwahNeilI like Wet Thingsxxxxxxxxxxxxxxxx
... water is a better thermal conducter than air.
The thermal conductivity of water is over twenty times greater than air, so if all other variables are equal then in water you’re going to lose heat much faster to your surroundings than in air.
I think you are correct SC regarding heat capacity. We might say that large masses of air or water have enormous heat capacity relative to the heat a sheep can produce, so heat capacity is not relevant, but there must be localized effects as you suggest that are significant in the heat transport mechanisms.Does "wind chill" depend on the heat capacity of air? I suspect it does.BTW, I know at least some air cooled engines "cheated" to some extent because they relied heavily on the lubricating oil to remove heat. The oil circuit included an oil cooler. VW advised against the use of multigrade oil in their air cooled cars for a long time. I believe this was because "straight" mineral oil recovers its lubricating properties, even after reaching rather high temperatures, whereas the additives in multigrade oils break down at high temperatures, and the oil's properties are permanently altered. Because of this, I installed an oil temperature gauge in my first VW, but it didn't prevent it from dropping a valve which went on to wreck the entire engine! (I think that was really more to do with the fact that the engine was completely worn out - what do you expect for 35 quid?)
Wet wool also has insulating properties → http://adventure.howstuffworks.com/wool-when-wet1.htm.