４年生(Eネイティブ)理科
Natural Sciences and Technology Grade 4-A
Matters and Materials
Chapter 3. Strengthening materials p.182
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とても簡単でとても大事な実験📜
ひらひらした一枚の紙も、形状が変わればその強度が変わります。
3.1 Ways to strengthen materials
There are different ways to strengthen materials to make a stronger structure. We can do this by changing the shape of the material. You may think that the shape may not make that much of a difference, but let's have a look. Which shape is stronger?
ACTIVITY: Explore different ways to strengthen paper
MATERIALS: •
Up to 5 sheets of A4 paper for each group
• Pieces of sticky tape
• A number of identical or similar size books for each group
INSTRUCTIONS
1. In groups of 4, investigate different ways of using your paper sheets to balance a book. 2. Look at the pictures below for some ideas3. Use a piece of sticky tape if you need it V4. How many different ways can you find of balancing a book more than 10 cm above the desk or floor, using only 1 sheet of A4 paper? You can try this on your own or in a small group.5. Once you think that you have found all the ways you can do it, choose a member of your group to report back to the rest of the class on the ways that you have found.6. With your teacher's help, show each different method side-by-side on a table or on the floor at the front of the class.
What did we learn from doing this activity? Materials can be made stronger by changing their shape. An example is rolling the paper into pillars. Pillars can be circular, triangular or square. Which one do you think is the strongest?