question_answer

A telescope has been adjusted for the relaxed eye. You are asked to adjust it for  the least distance of distinct vision, then how will you change the distance between the two lenses?

Answer:

                For relaxed eye, \[L={{f}_{0}}+{{f}_{e}}\]         (normal adjustment) For least distance of distinct vision, \[L'={{f}_{0}}+{{u}_{e}},\]\[{{u}_{e}}<{{f}_{e}}\] Therefore, \[L'<L.\] So the distance between the two lenses should be decreased.