Given, M=fef0=9 and f0+fe=20 fo=9fe So, 9fe+fe=20 ∴fe=2 cmfo=9×2f0=18 cm
The magnifying power of a telescope is 9. When it is adjusted for parallel rays the distance between the objective and eyepiece is 20 ~cm. The focal…
NEET UG 2012 — Physics Optics
2012mcqmedium
The magnifying power of a telescope is 9. When it is adjusted for parallel rays the distance between the objective and eyepiece is 20 cm. The focal length of lenses are
Official previous-year question
Held on 30 Apr 2012 · Verified 9 Jul 2026.
Options
- A
10 cm,10 cm
- B
15 cm,5 cm
- C
18 cm,2 cm
- D
11 cm,9 cm
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