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Question
Why should the objective of a telescope have large focal length and large aperture? Justify your answer.
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Solution
The objective of a telescope have large focal length and large aperture because large focal length enhances the magnifying power of the telescope and large aperture help in collecting large amount of light coming from the object so that a bright image is obtained.
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Useful Constants & Relations:
| 1 | Charge of a proton | e | 1.6 × 10-19 C |
| 2 | Speed of light in vacuum | c | 3 × 108 ms-1 |
| 1 u = 931 MeV | |||
