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Question
If this telescope is used to view the moon, what is the diameter of the image of the moon formed by the objective lens ? the diameter of the moon is 3.48 × 106 m and the radius of lunar orbit is 3.8 × 108m.
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Solution
Diameter of the image of the moon formed by the objective lens, d = α f0
`=>d=`
`=>d=(3.48xx10^6)/(3.8xx10^8)xx15`
⇒d=0.135 m = 13.5 cm
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