हिंदी

There are two beautiful lakes near a village. People come for boating and picnics in both the lakes. The village Panchayat is worried that with the noise of the boats the birds will stop coming.

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प्रश्न

There are two beautiful lakes near a village. People come for boating and picnics in both the lakes. The village Panchayat is worried that with the noise of the boats the birds will stop coming. The Panchayat wants motorboats in only one lake. The other lake will be saved for the birds to make their nests.

  • A longer boundary around the lake will help more birds to lay their eggs. So which lake should be kept for birds? Which lake should be used for boats?
एक पंक्ति में उत्तर
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उत्तर

The boundary around lake A is more than the boundary around lake B. So, lake A should be kept for birds and lake B should be used for boats.

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अध्याय 11: Area and its Boundary - Area and its Boundary [पृष्ठ १५६]

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एनसीईआरटी Math - Magic [English] Class 5
अध्याय 11 Area and its Boundary
Area and its Boundary | Q e) | पृष्ठ १५६

संबंधित प्रश्न

The farthest objects in our Universe discovered by modern astronomers are so distant that light emitted by them takes billions of years to reach the Earth. These objects (known as quasars) have many puzzling features, which have not yet been satisfactorily explained. What is the distance in km of a quasar from which light takes 3.0 billion years to reach us?


The principle of ‘parallax’ in section 2.3.1 is used in the determination of distances of very distant stars. The baseline AB is the line joining the Earth’s two locations six months apart in its orbit around the Sun. That is, the baseline is about the diameter of the Earth’s orbit ≈ 3 × 1011m. However, even the nearest stars are so distant that with such a long baseline, they show parallax only of the order of 1” (second) of arc or so. A parsec is a convenient unit of length on the astronomical scale. It is the distance of an object that will show a parallax of 1” (second) of arc from opposite ends of a baseline equal to the distance from the Earth to the Sun. How much is a parsec in terms of meters?


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3. Nano 103
4. SI Unit of time 10–9
5. Kilo Cubit

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Pencil of length
about 7 cm
   
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A bangle of perimeter
20 cm
   
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Do this for yourself and find the difference.


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What is the SI unit of length?


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