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The Human Eye and Colourful World
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04/12/2020 10:25 am
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If focal length of the objective and eye-piece of a telescope are 10 cm and 4 cm respectively, what will be its magnifying power in
(i) normal adjustments,
(ii) adjustment where image of distance object is formed at D? Given D = 25 cm.
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04/12/2020 10:28 am
Focal length of objective fo = 10 cm
Focal length of eyepiece fe = 4 cm
(i) In normal adjustment
m = fo/fe = 10/4 = 2.5
(ii) When the final image of distant object is at D, then
m = fo/fe(D + fe/D)
= 10/4(25+4/25)
= 2.9