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Magnification of microscope of objective...

Magnification of microscope of objective of focal length 5 mm is 400. If its tube length is 20 cm, then focal length of eye-piece is ......

A

200 cm

B

160 cm

C

2.5 cm

D

0.1 cm

Text Solution

Verified by Experts

The correct Answer is:
B, C
`m=(LD)/(f_0f_e)`
`thereforef_e=(LD)/(mf_0)` [`because` D=near point=25 cm]
`=(20xx25)/(400xx0.5)=2.5` cm
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