Naked Science Forum

General Science => General Science => Topic started by: newenglandguy on 04/07/2009 16:37:50

Title: Temperature Equilibrium of soil versu water
Post by: newenglandguy on 04/07/2009 16:37:50
Wanted to get some info, but I'm up in some remote area and can't get supplies.  I was going to show my grandson an experiment I remembered doing in high school.  We took soil and water and first refrigerator for so many minutes and then did the same with wafer.  Repeated the experiment with water.  Obviously the water would take to reach equilibrium would be different than soil, due to the fact that each have different densities.  Any one have any info as to how much the temperature difference would be versus time for each of the two materials?  Again, if I had access to a few thermometers I could do this, but I'm so remote I can't locate a couple of thermometers.

One part of the experiment involved heating both samples with a light bulb and the other was putting it in a fridge and cooling it for a bit.

Thanks

Dave
Title: Temperature Equilibrium of soil versu water
Post by: lyner on 06/07/2009 16:01:20
You would expect the times to equilibrium to be different but it's not directly to do with  density. It's to do with specific heat capacity, which relates to more issues than density (for instance, the shc of water is a lot higher than the shc of lead) and thermal conductivity.

Damp rock will have lower shc than water,almost certainly, but it will not convect, as cooling water will, so the core could take much longer to reach equilibrium.

Nice experiment to do on the kitchen table though. But explaining the results might be harder if your grandson is smart!!!