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Question
Write two important limitations of a refracting telescope over a reflecting-type telescope.
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Solution
Limitations of refracting telescope over reflecting type telescope:
- Refracting telescope suffers from chromatic aberration as it uses large-sized lenses.
- The image formed by refracting telescope is less bright than the image formed by the reflecting type telescope due to some loss of light by reflection at the lens and by absorption.
- The resolving power of refracting telescope is less than the resolving power of the reflecting type telescope as the mirror of the reflecting type telescope has a large diameter.
- The requirements of big lenses tend to be very heavy and therefore difficult to make and support by their edges.
- It is also difficult and expensive to make such large-sized lenses.
Notes
Students should refer to the answer according to their questions.
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