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Question
Can you think of how to cut a postcard so that you can pass through it?
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Solution
Yes, I can pass through a postcard by making a loop from it.
The steps are given below:
Make lines on the postcard as shown in this figure.
Cut the postcard along the lines which touch its border.
This will make a loop as shown here.
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Match the following.
| 1. | Length of the fore arm | metre |
| 2. | SI unit of length | second |
| 3. | Nano | 103 |
| 4. | SI Unit of time | 10–9 |
| 5. | Kilo | Cubit |
Fill in the following chart.
| Property | Definition | Basic Unit | Instrument used for measuring |
| Length | |||
| Mass | |||
| Volume | |||
| Time |
Rulers, measuring tapes and metre scales are used to measure ______
Guess the lengths to draw these things. Ask your friend to draw the same. After you make the drawing use a scale to measure the length. Whose drawing showed a better guess?
| Guess its length and draw |
Measure of your drawing |
Measure of your friend’s drawing |
| An ant of length less than 1 cm |
||
| Pencil of length about 7 cm |
||
| A glass 11 cm high with water up to 5 cm |
||
| A bangle of perimeter 20 cm |
||
| A curly hair of length 16 cm |
How many stamps can be placed along its length?
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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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.
- A longer boundary around the lake will help more birds to lay their eggs. So which lake should be kept for birds? Which lake should be used for boats?
Match the following:
| Prefix | Symbol | ||
| a. | Centi | i. | k |
| b. | Nano | ii. | c |
| c. | Mili | iii. | n |
| d. | Kilo | iv. | m |
Give some examples of larger length measures.
The distance between one end and the other end is called ______.
Yard was used as the unit of length.
The SI unit of mass is kg.
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?
