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The focal lengths of the objective and t...

The focal lengths of the objective and the eye-piese of an astronomical telescope are `0.25`m and `0.025`m, respectively. The telescope is focussed on an object 5 m from the objective, the final image being formed `0.25`m from the eye of the observer. Calculate the length of the telescope and its magnifying power.
[Hint : Mag. power = `v_(0)//u_(e)`]

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The correct Answer is:
`0.2859m,11.6`
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