- #1
vr_ben
- 3
- 0
Homework Statement
Alright so I am doing a fairly simple experiment testing how the temperature of water in a beaker effects how fast heat is lost. Have done the tests, but need to get some predicted results to compare them too.
Have been using a glass beaker filled with 200ml of water, beaker dimensions being 60mm diametre, 150mm tall, about 1.5mm thick (actually forgot to measure this, so if this is off let me know :P)
Thermal conductivity of glass: 0.8
The Attempt at a Solution
Ok so i used an equation for thermal current:
I = kA (Change in T/ Chane in x) with I being current (Watts) k being thermal conductivity, A being cross sectional area (i calcualted 28.27cm^2 but not sure if that's correct), T being temperature (Kelvin), x as distance current travels.
Anyway using that equation i calcualted it for a few different temperatures and got:
change in temp - Thermal current
70 - 10554.13W
60 - 9646.4W
50 - 7538.6W
40 - 6030.93W
30 - 4323.2W
20 - 3015.46W
And this is where I am sort of stuck. First of all are those reasonable numbers (seem quite high to me...)? and is there a way to convert W to degrees per second or minute or something which i could actually compare to real results?
Anyway if you read all that and can help in anyway way its much appreciated
thanks