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प्रश्न
a) Give two reasons to explain why reflecting telescopes are preferred over refracting type.
उत्तर
(a) The reflecting telescopes are preferred over refracting type because of the following reasons:
(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.
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संबंधित प्रश्न
Calculate the distance of an object of height h from a concave mirror of radius of curvature 20 cm, so as to obtain a real image of magnification 2. Find the location of the image also.
An object is kept on the principal axis of a concave mirror of focal length 10 cm. at a distance of 15
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(a) Virtual and magnified
(b) Virtual and diminished
(c) Real and magnified
(d) Real and diminished
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Mark the correct options.
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