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प्रश्न
Write two important advantages of reflecting telescope over a refracting telescope.
Explain two advantages of a reflecting telescope over a refracting telescope
State any one advantage ·of using a reflecting telescope in place of a refracting telescope.
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उत्तर १
The two advantages of a reflecting telescope over a refracting telescope are as follows:
(i) There is no chromatic aberration in case of reflecting telescopes as the objective is a mirror.
(ii) Spherical aberration is reduced in case of reflecting telescopes by using mirror objective in the form of a paraboloid.
उत्तर २
Two advantages of a reflecting telescope over a refracting telescope are:
1) Chromatic aberration is absent in reflecting type telescope whereas it is present in refracting type telescope. The absence of chromatic aberration in reflecting type telescope is because the objective is a mirror.
2) Images are brighter compared to that in a refracting type telescope.
उत्तर ३
Reflecting telescope remove chrometic and spherical aberration.
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संबंधित प्रश्न
A small telescope has an objective lens of focal length 140 cm and an eyepiece of focal length 5.0 cm. What is the magnifying power of the telescope for viewing distant objects when
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- the final image is formed at the least distance of distinct vision (25 cm)?
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A small telescope has an objective lens of focal length 150 cm and an eye piece of focal length 5 cm. If this telescope is used to view a 100 m high tower 3 km away, find the height of the final image when it is formed 25 cm away from the eye piece.
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In a telescope, the lens facing the object is called the:
In an astronomical (refracting) telescope, the objective lens has:
Which type of telescope uses two convex lenses, with a large objective and a small eyepiece?
