Completed in 1895, the Yerkes telescope operated by the University of Chicago remains the biggest...

Completed in 1895, the Yerkes telescope operated by the University of Chicago remains the biggest (largest-diameter) refracting telescope ever built. Figure P26.55 shows a photograph of the telescope taken in 1921, when it was the most important astronomical instrument in the world. The refractor has an f-number of 19 and an objective lens that measures 1.02 m across. What are the focal length and approximate length of this telescope? Do your calculations agree with an estimate made from the photograph?

Figure P26.55 Albert Einstein and observatory staff stand in front of the Yerkes 40-in. refracting telescope in 1921.