A question on "The Focal-Length of a Lens" 1. The problem statement, all variables and given/known data Basically, I have a piece of cousework due in later today (don't ask me why I left it so late), and I was told by a friend that in the analysis and conclusion that she was told by a teacher to include a section called "Physics Principles and Concepts used", one which I have never heard of before. I would also be grateful for any general information relating as to what topics/sub-headings I should actually include in the Analysis + Evaluation, as well as about the properties of the image produced. 2. Relevant equations 1/u + 1/v = 1/f y = mx + c 1/f = 1/c Please bear with me, as my maths is somewhat weak. 3. The attempt at a solution For more background information of this experiment, my plan can be found here in a PDF. (the plan is already handed in, so I do not require any assistance with it). Current version can be found here; please note that I will be working on this live, so the version in the link will change according to your suggestions. Thank you in advance, cbs27 Notate Bene: I am not asking for this to be done for me. I fully understand the policies of these fora, and want to respect them. This request is now VOID, and all links have been taken down.