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The length of a telescope is 36 cm . The...

The length of a telescope is 36 cm . The focal lengths of its lenses can be

A

`30` cm, `6` cm

B

`-30` cm, `-6` cm

C

`30` cm, `-6` cm

D

`-30` cm, `6` cm

Text Solution

Verified by Experts

The correct Answer is:
A
Length of a telescope, `L=f_(0)+f_(e)=36` cm
and both the lenses are convex.
`:. F_(0)=30` cm, f_(e)=6` cm.
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