1. The problem statement, all variables and given/known data An object is 1 m from a screen. At what points may a 0.05-m focal length lens be placed so as to produce a sharp image on the screen? What are the corresponding magnifications? 2. Relevant equations Lens maker equation: 1/s + 1/s' = 1/f Magnification equation: m = -s'/s = -f/s 3. The attempt at a solution For the first question: 1/s' = 1/f -1/s = 1/0.05 m-1 = -.95 m. 1 m - .95 m = 0.05 m away from the screen. Magnification: m = -0.05 m / 1 m = -0.05 Is this right?