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प्रश्न
(i) What is meant by resolving power of a telescope?
(ii) State any one method of increasing the resolving power of an astronomical telescope.
उत्तर
(i) Resolving power is the reciprocal of the smallest angular separation between two distant object which can be observed distinctly using a telescope.
If θ `[=(1.22lambda)/D]` be the angular separation, then resolving power = `1/theta = D/(1.22lambda)`;
[D =Aperture of objective lens]
(ii) By taking large aperture i.e., increasing the size of the aperture the resolving power of lens is increased.
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संबंधित प्रश्न
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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Read the following paragraph and answer the questions.
| A number of optical devices and instruments have been designed and developed such as periscope, binoculars, microscopes and telescopes utilising the reflecting and refracting properties of mirrors, lenses and prisms. Most of them are in common use. Our knowledge about the formation of images by the mirrors and lenses is the basic requirement for understanding the working of these devices. |
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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.
Draw a labelled ray diagram showing the image formation by a refracting telescope. Define its magnifying power.
