MCQ
All of the following statements are correct except
  • A
    The total length of an astronomical telescope is the sum of the focal lengths of its two lenses
  • The image formed by the astronomical telescope is always erect because the effect of the combination of the two lenses is divergent
  • C
    The magnification of an astronomical telescope can be increased by decreasing the focal length of the eye-piece
  • D
    The magnifying power of the refracting type of astronomical telescope is the ratio of the focal length of the objective to that of the eye-piece

Answer

Correct option: B.
The image formed by the astronomical telescope is always erect because the effect of the combination of the two lenses is divergent
b
(b) Final image formed by astronomical telescope is inverted not erect.

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