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An opera glass (Galilean telescope ) mea...

An opera glass `(`Galilean telescope ) measures `9cm` from the objective to the eyepiece. The focal length of the objective is `15 cm`. Its magnifying power is

A

`2.5`

B

`2//5`

C

`5//3`

D

`0.4`

Text Solution

Verified by Experts

The correct Answer is:
A
`f_(o)-f_(e)=9cm` and `f_(e)=f_(o)-9=15-9=6cm`
`impliesm=(f_(e))/(f_(e))=(15)/(6)=2.5`
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