1. The problem statement, all variables and given/known data Focal length of a concave mirror. This was an experiment, done in class. I was required to collect a light globe:(of course with a power source) for the object, paper:screen/image, and a concave mirror. I created the images, of the globe filament, to the screen, and measured. I took 5 trials of V and U, where; U=Object distance, and V= Image distance. The results were; 1.)V=25.0, U=38.0 2.)V=22,0, U=47.0 3.)V=20.0, U=57.5 4.)V=18.5, U=75.0 5.)V=18.0, U=88.5 From here, I could use the graphics calculator (1/v for y-axis, and 1/u for x-axis), or 1/f=1/v+1/u for each and average them. Question 1.: What is the graphical method (calculator.)? Question 2.: What is the Mirror equn method? Question 3.: Why is the graphical method more accurate, than 1/f=1/v+1/u? 2. Relevant equations 1/f=1/v+1/u 3. The attempt at a solution 1.) stat, 1/u for list1, 1/v for list2, GRPH, GPH1, X, Copy, Menu, GRAPH, Y=-1.0522075X+0.067, Enter, G solv, Xcal- when Y=0, Ycal- when X=0. Then f=1/yintercept and f=1/xintercept for focal length. 2.) average values (of 1/f=1/v+1/u).