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प्रश्न
How many stamps can be placed along its length?
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उत्तर
Measure the length of the stamp already placed on it with the help of a ruler.
Length of stamp = 2 cm.
Thus, we can place 7 stamps along the length of the rectangle.
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संबंधित प्रश्न
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?
Complete the analogy.
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Measure of your drawing |
Measure of your friend’s drawing |
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||
| Pencil of length about 7 cm |
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| A glass 11 cm high with water up to 5 cm |
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| A curly hair of length 16 cm |
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- How many kilometers long is the actual boundary of lake A?
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.
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Why is Earth's orbit used instead of its diameter to measure distances to stars using the parallax method?
One parsec is defined as ______.
