An observer is using an astronomical refracting telescope to observe planets in normal adjustment. The focal lengths of the objective and eyepiece used in the telescope construction are \(20\) m and \(2\) cm respectively. Consider the following statements about the telescope:
(a) the distance between the objective and the eyepiece is \(20.02\) m.
(b) the magnification of the telescope is \(-1000\).
(c) the image of the planet is erect and diminished.
(d) the aperture of the eyepiece is smaller than that of the objective.
 
The correct statements are:
1. (a), (b), and (c) 2. (b), (c), and (d)
3. (c), (d), and (a) 4. (a), (b), and (d)
Subtopic:  Telescope |
 64%
From NCERT
NEET - 2022
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In an astronomical telescope in normal adjustment, a straight line of length \(L\) is drawn on the inside part of the objective lens. The eye-piece forms a real image of this line. The length of this image is \(l.\) The magnification of the telescope is:
1. \(\frac{L}{l}+1\)
2. \(\frac{L}{l}-1\)
3. \(\frac{L+1}{l-1}\)
4. \(\frac{L}{l}\)

Subtopic:  Telescope |
 59%
From NCERT
NEET - 2015
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An astronomical refracting telescope will have large angular magnification and high angular resolution when it has an objective lens of:

1. small focal length and large diameter.
2. large focal length and small diameter.
3. large focal length and large diameter.
4. small focal length and small diameter. 

Subtopic:  Telescope |
 60%
From NCERT
NEET - 2018
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An astronomical telescope has an objective and eyepiece of focal lengths \(40\) cm and \(4\) cm respectively. To view an object \(200\) cm away from the objective, the lenses must be separated by a distance:
1. \(46.0\) cm 2. \(50.0\) cm
3. \(54.0\) cm 4. \(37.3\) cm
Subtopic:  Telescope |
 63%
From NCERT
NEET - 2016
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