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Question
How is the working of a telescope different from that of a microscope?
Solution
A microscope is used to look into smaller details like structure of cells etc. On the other hand, a telescope is used to see larger objects that are very far away like stars, planets etc.
Telescope mainly focuses on collecting the light into the objective lens, which should thus be large, while the microscope already has a focus and the rest is blurred around it.
There is a big difference is in their magnification factors.
For telescope the angular magnification is given by `M = f_0/f_e`
Where f0 is the focal length of the objective lens and fe is the focal length of the eyepiece. For microscope the angular magnification is given by
`M= 1+D/f_0`When image if formed at distance of least distinct vision
`M= D/f_0`When image is formed at infinity
Where D is the distance of least distinct vision and f0 is the focal length of objective lens. Magnifying power of compound microscope
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RELATED QUESTIONS
Draw a schematic ray diagram of a reflecting telescope showing how rays coming from a distant object are received at the eyepiece.
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| L1 | 3 | 8 |
| L2 | 6 | 1 |
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| There are two types of optical instruments: Microscopes and Telescopes. Microscopes are used to magnify very tiny objects whereas telescopes are used to study distant objects. Both of them deploy convex lenses. In his telescope, Newton used a large parabolic mirror to collect light from the stars and reduce aberrations. |
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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 | |||
