Hello! I am a grade 12 student. If you are familar with the IB program, I am writing an extended essay (it's a 4000 word research essay) on how transformer losses are affected by temperature. Through two experiments I was able to determine how the losses of the primary and secondary windings of a transformer change as temperature increases. In my first experiment I connected the windings in series with each other as well as in series with a 20.0 ohm load. The windings were submerged in hot water. I let the water cool as I collected data. I used the data I collected from this to find how the resistance of the windings increases with temperature and how the increasing resistances decreased the power to the load. In the second experiment, I set up the transformer and connected the primary windings directly to a constant voltage source. The transformer was submerged in hot water. The water was allowed to cool to collect data for a range of temperatures (between 20 and 70 degrees). I connected the secondary windings directly to the 20 ohm load. I measured to current and voltage in to the primary windings, as well as the voltage and current to the load. I found the change in primary winding losses with temperature by looking at how the power in decreased with the increasing resistance of the windings. I was able to find the secondary winding losses and how they changed with temperature by calculating the power the would have been supplied to the load if the windings had no resistance minus the actual power to the load. (I could calculate the expected resistance from the temperature coefficent of the copper wires.) Now I am trying to figure how to isolate the core losses from the data that I gathered. I was thinking that I could use: [Change in core losses from 20° to a given temperature] = [change in power to the load to from 20° to a given temperature] - [change in primary winding losses from 20° to a given temperature] - [change in secondary winding losses from 20° to a given temperature] The results of this indicated that: -Primary and secondary winding losses are directly proportional to temperature -Core losses decrease directly with temperature I found it strange that the rate of change of core losses with temperature seemed to be the same as the rate of change of primary winding losses with temperature. Might this indicate a flaw in my approach to calculate the core losses? Does this make sense? Or is it not possible to isolate the core losses? Also, do any of the things I've done sound incorrect? Any help would greatly be appreciated!