Verified Solution • 2025–26 Session
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QNEET-2022-Ph-554: NEET 2022 Physics - Class 12 NEET-2022-Ph-554 Solution: An astronomical refracting telescope is being used by an…
An astronomical refracting telescope is being used by an observer to observe planets in normal adjustment. The focal lengths of the objective and eye piece used in the construction of the telescope are 20 m and 2 cm respectively. Consider the following statements about the telescope: (a) The distance between the objective and eye piece is 20.02 m (b) The magnification of the telescope is (-) 1000 (c) The image of the planet is erect and diminished (d) The aperture of eye piece is smaller than that of objective The correct statements are: (a) (b) and (d) (a) (b) and (c) (b) (c) and (d) (c) (d) and (a)
Multiple Choice Options
- A (a), (b) and (d)
- B (a), (b) and (c)
- C (b), (c) and (d)
- D (c), (d) and (a)
Step-by-Step Verified Solution
Given f 0 = 20 m = 2000 cm, f e = 2 cm
_ Distance between objective and eye piece
l = f 0 + f e
= 20 m + 2 cm = 20.02 cm
_ Magnification of telescope
m = _ f 0 f e = _ 2000 c m 2 c m = _ 1000
_ Image formed by telescope is inverted.
_ Aperture of eye piece is smaller than that of objective.
So, statements (a), (b) and (c) are correct.