(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Alright so im 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

3. 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 thats 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 im 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

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# Homework Help: Predicting heat loss

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