Question
An astronomical refracting telescope will have large angular magnification and high angular resolution, when it has an objective lens of
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Answer
For telescope, angular magnification $=\frac{f_{0}}{f_{e}}$
Angular resolution $=\frac{D}{1.22 \lambda}$ should be large.
So, objective lens should have large focal length $\left(f_{o}\right)$ and large diameter $D$ for large angular
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