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 length of lenses are
Held on 30 Apr 2012 · Verified 9 Jul 2026.
10 cm,10 cm
15 cm,5 cm
18 cm,2 cm
11 cm,9 cm
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