Hey guys, 1. The problem statement, all variables and given/known data Im doing my physics coursework atm and its on the subject of Solar cells and am changing a few variables and observing how the voltage of the solar cell changes. Im also measuring the current and using that to calculate the Power output. the caluclations are easy, its explaining why my data is the way it is is the issue. the first thing i did was rotate the solar cell in 10 degree increments relative to the light source. the power output vs rotation looked like the following: http://img821.imageshack.us/img821/4315/rotation.jpg [Broken] (sorry for the drawing, i dont have the graphs at hand). The other graph was a power against an increasing load resistance. on the graph, the power shot up and then slowly decreased, which, to me suggested i ought to use a logarithmic axis scale (base 10). this graph looked like this: http://img651.imageshack.us/img651/5102/rload.jpg [Broken] Any ideas why it does this and the physics behind it? Thanks for any help, its much appreciated. any issues with the image hosting, just say and ill try to find an alternate host. EDIT: just incase i didnt make it clear, in all of these graphs, power is on the y axis and rotation or Rload is on the x. EDIT2: just saw the dodgy looking title. how do i change it?