EVALUATION:
Although I feel that my experiment was sound overall, I thought there were many points at which the accuracy was not perfect. As I have already stated, my preliminary experiment was not accurate enough to justify being used as my main experiment, mostly due to the fact that I was relying on all the bubbles being the same size, which they clearly weren´t, however many of the smaller inaccuracies also apply to my main experiment. Firstly, the distance between the light sources and the Canadian Pondweed were not measured to a very high degree of accuracy, especially when you note the fact that the distance should have been measured exactly from the filament of the light bulb to the centre of the plant, and it is possible here to find a percentage error. I estimate that the error could have been up to0.5cm.
Although I was not actually using the distances as part of my results, I used them as a marker for where the lamp was placed each time, as I assumed that the light intensity would be the same each time at a particular distance. …