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प्रश्न
How is the working of a telescope different from that of a microscope?
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उत्तर
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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संबंधित प्रश्न
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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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Read the following paragraph and answer the questions.
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- Write two points of difference between a compound microscope and an astronomical telescope
OR
Write two distinct advantages of a reflecting type telescope over a refracting type telescope.
The magnifying power of an astronomical telescope in normal adjustment is 2.9 and the objective and the eyepiece are separated by a distance of 150 cm. Find the focal lengths of the two lenses.
Read the passage given below and answer the question that follows.
| 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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What is the difference between a compound microscope and an astronomical telescope (refracting type), as far as their lenses are concerned?
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 | |||
An optical instrument that uses objective and eyepiece lenses to magnify distant terrestrial or celestial objects is called a:
During the formation of an image in a telescope under normal adjustment, the eyepiece is adjusted so that the intermediate image lies:
