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प्रश्न
Now cut strips of equal sizes out of it. Using tape join the strips, end to end, to make a belt.
How long is your belt? _________
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उत्तर
The belt is 84 cm long.
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संबंधित प्रश्न
When the planet Jupiter is at a distance of 824.7 million kilometres from the Earth, its angular diameter is measured to be 35.72″ of arc. Calculate the diameter of Jupiter
Just as precise measurements are necessary in science, it is equally important to be able to make rough estimates of quantities using rudimentary ideas and common observations. Think of ways by which you can estimate the following (where an estimate is difficult to obtain, try to get an upper bound on the quantity):
the number of strands of hair on your head
Match the following.
| Column A | Column B |
| (1) Length | a. kilogram |
| (2) Mass | b. cubic metre |
| (3) Area | c. metre |
| (4) Volume | d. square metre |
Solve the numerical example.
When the planet Jupiter is at a distance of 824.7 million kilometers from the Earth, its angular diameter is measured to be 35.72'' of arc. Calculate the diameter of Jupiter.
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How wide is the rectangle? ________ cm
How close was your earlier guess? Discuss.
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- Which team could make more children sit in their square? How many?
Chumki, Jhumri, and Imran need wire to make a fence.
- How much wire in all will the three need?
So Anar also tried many different ways to make a boundary for 800 square meters of land.
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- A
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Gold wire for B = _________ metres - C
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- D
So he will get __________ metres of gold wire!!
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- How many kilometers long is the actual boundary of lake B?
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- Find the area of lake B on the drawing in square cm. What is its actual area in square km?
The SI unit of mass is kg.
To measure the distance of a planet from the earth, ______ method is used.
Consider a sunlike star at a distance of 2 parsecs. When it is seen through a telescope with 100 magnification, what should be the angular size of the star? Sun appears to be (1/2)° from the earth. Due to atmospheric fluctuations, eye can’t resolve objects smaller than 1 arc minute.
According to the modern definition, what fraction of a second does light travel to define one metre?
Which instruments are used to measure very small distances at the atomic scale?
