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प्रश्न
Difference in size 
Do this for yourself and find the difference.
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उत्तर
Different in size: 1.82 m – 1.52 m
= 0.30 m
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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?
Write true or false.
Every measurement involves two things – a number and a unit.
500 gm = ______ kilogram.
Match the following.
| 1. | Length | kelvin |
| 2. | Mass | metre |
| 3. | Time | kilogram |
| 4. | Temperature | second |
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| Guess its length and draw |
Measure of your drawing |
Measure of your friend’s drawing |
| An ant of length less than 1 cm |
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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 bangle of perimeter 20 cm |
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| A curly hair of length 16 cm |
How close was your earlier guess? Discuss.
Arbaz plans to tile his kitchen floor with green square tiles. Each side of the tile is 10 cm. His kitchen is 220 cm in length and 180 cm wide. How many tiles will he need?
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So Anar also tried many different ways to make a boundary for 800 square meters of land.
He made rectangles A, B, and C of different sizes. Find out the length of the boundary of each. How much gold wire will he get for these rectangles?
- A
Gold wire for A = _________ metres - B
Gold wire for B = _________ metres - C
Gold wire for C = __________ metres
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- D
So he will get __________ metres of gold wire!!
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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What formula is used to measure the area of your classroom?
Give some examples of larger length measures.
The distance between one end and the other end is called ______.
The Unit used to measure length ______.
Larger unit for measuring time is ______.
The SI unit of mass is kg.
If a planet subtends an angle α at distance D, what formula is used to find the planet's diameter?
