This is a simple experiment to measure the "specific heat" (also called "specific heat capacity") of any fluid. In addition to the principle of specific heat, the experiment also demonstrates some basic electrical principles such as Ohm's law.

Specific heat is typically quoted in units of J/g/K or J/g/degreeC (Joules per gram per Kelvin or Joules per gram per degree Celcius). For example, if a substance has a heat capacity of 2 J/g/degreeC that means it takes 2 Joules of energy to raise the temperature of 1 gram of the substance by 1 degree Celcius. Note that when we are talking about temperature changes rather than absolute temperatures, a Kelvin is the same as a degree Celcius.

Why would you want to know the specific heat of a fluid? Well, suppose you want to Build your own flat panel solar thermal collector and you'd like to find or create a fluid that can store lots of energy for a small change in temperature. You might want to experiment with different fluid compositions to see what has the highest specific heat.

Step 1: Equipment

For this experiment you will need the following
  • Digital postal scale
  • Plastic cup that will hold at least 250ml
  • Variable power supply]
  • Digital thermometer with probe
  • 7.5 ohm, 5W resistor] (or something close)
  • Short length of wire
  • Clock showing time in seconds (not shown)
  • 250 ml of cold water (tap water will do, distilled is better) (not shown)
<p>How to measure the Cp of air??</p>
There is no such thing as a "degree Kelvin". Only Kelvin.
Thanks. Fixed. Did you created your user account just to tell me that?
Yes, all in the name of science!
Just as I suspected...
...You are...umm...EATING!
OK...I'll tell you what it means...the suspense has been building long enough...OK, are y'all ready for this...OK...brace yourselves... OK, I first said it was lame, as you can see above, where it says "lame", but then I re-examined the instructable and found it to be not so lame, so I had to 'eat my words' so to speak, so if I was going to have to 'eat my words' as I have said, then I was going to 'make a "meal" of it', so to speak, and, conveniently, the letters of lame, rearanged, spell meal, so I did not even have to cook up a new message to make a "meal" of it, rather just use the ingredients I had on hand, mixing up the 'l', the 'a', the 'm' and the 'e' to produce a "meal" clever, no?
yeah, eat that...ah ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha ha...wait, I haven't finished...ha ha ha ha ha ha ha ha ha ha ha ha...get it, eat that...ah ha ha ha ha ha ha ha ha ha ha...classic
im just glad aliens took over pluto
I learned this stuff in chemisty using heated metals. Great instructable coverage.
Nice! Very nicely done. Kudos to you on format and explanation. I like how you relate this instructable to the solar water heating instructable. I am also really impressed with your final step where you cover error sources, improvements and further reading. A+

About This Instructable




Bio: I have a B.A.Sc and M.Eng. from the University of British Columbia, specializing in electromechanical design, but mostly I like to tinker ... More »
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