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phamhachi01
2 năm trước
giúp mik vs ạ, cảm ơn mn Câu 11: Một cuộn dây bằng đồng dài 125m và tiết diện S=0,5mm2. a) Tính điện trở của cuộn dây. Biết điện trở suất của đồng là ρ=1,7.10-8 Ωm. b) Cắt cuộn dây trên ra làm hai đoạn, đoạn thứ nhất dài gấp 4 lần đoạn thứ hai, sau đó mắc lần lượt chúng vào hai cực của nguồn điện có hiệu điện thế U=4,25V. Tính dòng điện qua mỗi đoạn dây.
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IV. a) Read then write True or False Greert Vinck is 29 years old. He lives in Belgium. He has collected teabags since he was five years old. Now he has more than 12,000 teabags. Perhaps you think it is strange to collect teabags, but a lot of people do this. There are about 200 teabag collectors in Belgium and the Netherlands. Greert Vinck also exchanges teabags with people from France, Germany, Switzerland, Italy, Spain, Greece, Sweden, Iceland, the USA, Canada, Brazil and Argentina. If you hobby is collecting teabags, why not exchange them with him? 1. Greert Vinck is 29 years old. 2. He started to collect teabags when he was 24 years old. 3. He owns over 12,000 teabags. 4. He collects teabags and nobody does this. 5. Belgium has about 100 teabag collectors. 6. People from Germany don’t want to exchange teabags with him. 7. He exchanges teabags with some Spanish collectors. 8. He wants you to exchange teabags with him. b) Read again and choose A, B or C 1. He has collected teabags since he was five years old means A. he collected teabags when he was 5, but he doesn’t collect them now B. He collected teabags for 5 years C. He started to collect teabags when he was 5 and he still collects them now 2. We use perhaps when A. we are not sure B. we are sure C. we are 100% sure 3. The word strange means A. usual B. unusual C. unusually 4. The word exchanges means A. gives sb st B. sends sb st C. gives sb st and receive the same thing from them 5. We use the verb to exchange in the structure A. to exchange st with sb B. to exchange sb st C. to exchange sb with st 6. The sentence “a lot of people do this” means A. a lot of people exchange this B. a lot of people collect teabags C. a lot of people exchange teabags 7. Which sentence is true? A. He exchanges teabags with a lot of collectors from Asia B. He exchanges teabags with a lot of collectors from Africa C. He exchanges teabags with a lot of collectors from Europe, North America and South America 8. The word them in the last sentence refers to A. teabags B. people C. Geert Vinck

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