This is an old revision of the document!
Two screencasts show how to set up a spreadsheet for computing the power consumption of a resistor in a circuit of four resistors in series and parallel combinations. The first screencast is a narrated set of slides giving the equations used in the analysis. The second screencast shows how to set up an Excel spreadsheet to perform the calculations and make a simple plot.
These screencasts were made in 2010. The Excel demo used Excel 2003 for Windows. There is no difference in basic functionality with Excel 2007 or Excel 2010 for Windows or Excel 2011 for Macintosh. However the user interface is different for each of these versions, which means that you may have to hunt for the commands demonstrated in the screencast. The same commands are in all versions, but the “improved” user interface makes some of those commands harder to find.