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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
500 gm = ______ kilogram.
A hand span is a reliable measure of length.
Rulers, measuring tapes and metre scales are used to measure ______
Metre is the unit of ______.
Difference in size 
Do this for yourself and find the difference.
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You can play this game on the ground. Make two squares of one square meter each. Divide your class into two teams. Ready to play!
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- Which team could make more children stand in their square? How many?
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- How many cm is the length of the boundary of lake A in the drawing?(use thread to find out)
Length is a fundamental quantity.
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The Unit used to measure length ______.
SI unit of electric current is ______.
The SI unit of mass is kg.
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In an experiment to estimate the size of a molecule of oleic acid 1 mL of oleic acid is dissolved in 19 mL of alcohol. Then 1 mL of this solution is diluted to 20 mL by adding alcohol. Now 1 drop of this diluted solution is placed on water in a shallow trough. The solution spreads over the surface of water forming one molecule thick layer. Now, lycopodium powder is sprinkled evenly over the film and its diameter is measured. Knowing the volume of the drop and area of the film we can calculate the thickness of the film which will give us the size of oleic acid molecule.
Read the passage carefully and answer the following questions:
- Why do we dissolve oleic acid in alcohol?
- What is the role of lycopodium powder?
- What would be the volume of oleic acid in each mL of solution prepared?
- How will you calculate the volume of n drops of this solution of oleic acid?
- What will be the volume of oleic acid in one drop of this solution?
According to the modern definition, what fraction of a second does light travel to define one metre?
If a planet subtends an angle α at distance D, what formula is used to find the planet's diameter?
