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In a terrestrial telescope, the focal le...

In a terrestrial telescope, the focal length of objective is `90cm`, of inverting lens is `5 cm` and of eye lens is `6 cm`. If the final image is at `30cm`, then the magnification will be the final image is at `30cm, ` then the magnification will be

A

21

B

12

C

18

D

15

Text Solution

Verified by Experts

The correct Answer is:
C
`m=(f_(o))/(f_(e))(1+(f_(e))/(D))impliesm=(90)/(6)(1+(6)/(30))impliesm=18`
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