Question: You have learned (or will learn) in optics that certain lenses (namely, thin spherical lenses) can be characterized by a parameter called the focal length f and that if an object is placed at a distance p from the lens, the lens forms an image at a distance q, satisfying the lens equation, 1/f = (11p) + (11q), where f always has the same value for a given lens. To check if these ideas apply to a certain lens, a student places a small light bulb at various distances p from the lens and measures the location q of the corresponding images. She then calculates the corresponding values off from the lens equation and obtains the results shown in Table. Make a plot of f against p, with appropriate error bars, and decide if it is true that this particular lens has a unique focal length f
