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How is the Working of a Telescope Different from that of a Microscope?

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Question

How is the working of a telescope different from that of a microscope?

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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 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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2011-2012 (March) Delhi Set 1

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    1 u = 931 MeV

A small telescope has an objective of focal length 140 cm and an eye piece of focal length 5.0 cm. The magnifying power of telescope for viewing a distant object?


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