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प्रश्न
How many stamps are needed to cover the rectangle?
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उत्तर
The number of stamps that can be placed in the rectangle
= 7 × 4
= 28
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संबंधित प्रश्न
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
While measuring the length of an object using a ruler, the position of your eye should be
A hand span is a reliable measure of length.
While measuring the length of a sharpened pencil, the reading of the scale at one end is 2.0 cm and at the other end is 12.1 cm. What is the length of the pencil?
Which line is longer? C or D? Measure each line. How good is your guess?
How many stamps can be placed along its length?
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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- What is the length of the boundary of lake B in the drawing?
What are the materials needed to find the length of a banana?
Give some examples of larger length measures.
Length is ______.
SI unit of electric current is ______.
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To measure the distance of a planet from the earth, ______ method is used.
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?
In the parallax formula D = b/θ, what must be true about the angle θ for the calculation to be correct?
If a planet subtends an angle α at distance D, what formula is used to find the planet's diameter?
