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When a telescope is adjusted for paralle...

When a telescope is adjusted for parallel light, the distance of the objective from the eye piece is found to be `80 cm`. The magnifying power of the telescope is 19 . The focal length of the lenses are

A

`61 cm, 19 cm`

B

`40 cm, 40 cm`

C

`76 cm, 4 cm`

D

`50cm, 30 cm`

Text Solution

Verified by Experts

The correct Answer is:
C
`f_(o)+f_(e)=80` and `(f_(o))/(f_(e))=19impliesf_(o)=76` and `f_(e)=4cm`
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