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प्रश्न
Answer the following question in detail.
What is a terrestrial telescope and an astronomical telescope?
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उत्तर
- Telescopes used to see the objects on the Earth, like mountains, trees, players playing a match in a stadium, etc. are called terrestrial telescopes.
- In such a case, the final image must be erect. The eye lens used for this purpose must be concave and such a telescope is popularly called a binocular.
- Most of the binoculars use three convex lenses with proper separation. The image formed by the second lens is inverted with respect to the object. The third lens again inverts this image and makes the final image erect with respect to the object.
- An astronomical telescope is the telescope used to see objects like planets, stars, galaxies, etc. In this case, there is no necessity for an erect image. Such telescopes use a convex lens as an eye lens.
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