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物理 高校生

名問の森の質問です! ?のところのV1とV2の向きがなぜそうなるか分からないので教えて下さい!

122 電磁気 38 電磁誘導 十分に長い直線導線Lがy軸上 にあり, 1辺の長さ2aの正方形コ イル ABCD が 辺ABをx軸上に, 辺BC を軸に平行にして置かれて いる。 コイルの電気抵抗は R で, コ イルの位置は辺ABの中点Mの座 標xで表す。 装置は真空中に置かれ, 真空の透磁率 μlo とする。 コイルの 自己誘導は無視する。 Foll 導線L に+yの向きに一定電流Iを流し,コイルを一定の速さ で,xy平面上,x軸に沿って導線から遠ざける。コイルがx(a)の 位置を通過するときについて, (1) L による,点A,B での磁場の強さ H1, H2 をそれぞれ求めよ。 (2) コイル全体での誘導起電力の向き (時計回りか反時計回りか)と大 きさVを次の2つの方法で求めよ。 Level (1)★★ (2) (a)★ (b)★ (3)★ Point & Hint 電磁誘導は一般にはファラデーの電磁誘導 の法則に従っている 0 (2) (b) 微小時間⊿tの間の磁束の変化⊿のを調 べる。 といっても, コイルを貫く磁束のはコイ ル内の磁場が一様ではないので(積分しない限 り) 計算できない。 そこで, 変化した部分だけ に目を向ける。 近似の見方も必要。 L D A -2a- M C B (a) 1つ1つの辺に生じる誘導起電力を調べる。 (b) コイルを貫く磁束の変化を調べる。 (3) x=2aのとき, コイルに加えている外力の向きと大きさを求め よ。 (九州大+お茶の水女子大) -V Base 電磁誘導の法則 磁束① = BS V=-N40 4t 一面積S N巻きコイル ※マイナスは磁束の変化を 妨げる向きに誘導起電力 が生じることを表す。 LECTURE (1) A,Bでの磁場は ? I H₁ = 2π (x− a) 2π (x+a) (2a) 直線電流Ⅰのつくる磁場は紙面の裏へ の向きとなり、磁力線を切って進む AD と BCで誘導起電力 V1, V2が図の向きに発生 している。公式V=vBlより V₁ = vμoH₁.2a V2= vμoH22a 2つの起電力が逆向きとなっていることと, H>Hより全体の起電 力は時計回りで (b)微小時間tの間にコイルはx=v4t だ け動き,右の赤色部分で磁束を402 増やし、 灰色部分で4の減らす。 そこで,磁束の変化 40は H2= 40= 40₂ 40₁ =μoH22a4xμoHi・2a4x 2μo lav π (x²-a²) At 符号マイナスは磁束の減少を表している (H) > H2 より定性的にも明らか)。 よっ て, 誘導起電力の向きは、父の向きの磁場 を生じるようにコイルに電流を流す向きで あり、時計回りと決まる。 40=2μoIav V = π (x² - a²) 4t V=V1-V2=2μova (H1-H2)= 2μo Iav π (x²-a²) (3) x=2a より V= 2μo Iv であり、誘導電流 3π えは時計回りに流れ, オームの法則より i = R 38 電磁誘導 2μo Iv 3πR V₁ H₁ v A -x+a H₁ 4x F D 123 H 2 V i V2 A ⊿xは微小なので ③ 磁場はHやHで 一定としてよい。 B H2 4x C i F2 B Iとの向きから, ③ F は引力, F2は反 発力と決めてもよい。

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英語 高校生

grammar collectionの第11章接続詞のpracticeの答えをしりたいです🙇

n #1 Practice ① 英文中の空所に入る適切な語または語句を選択肢から選びなさい。 1. They are not crazy, () are they fools. 1 or 2 nor 3 both 102 2. Hurry up, ( ) you will be in time for the train. 1 and 2 if 3 or 3. He is always busy ( ) within and outside the country. 4 and both <東邦大) both of 2 the both 3 both plnil vsy and yuuuoo eid ),19tew to vinslq eri vunos 16AT 4. Many students in the class could ( ) locate the country on the map nor name its capital 79V9WOD city. 1 both 2 either 3 longer OHNSON VEL 5. () Bill accepted our offer was a big surprise to us. 1 When 2 If 3 What 7. The waiter asked me ( ) I would like some coffee. 1 if that 3 what glidw 8. He asked me ( 1 whether 4 That 6. His new movie is different from his last one, ( ) it's based on a true story. 1 in that 2 for that 3 of which with which ) she was coming or not. 2 then 3 what 9. I like to go up in the mountains ( 2 when 1 however Point 10. I have known that gentleman () he was a little boy. 1 when 2 from 3 during either 4 but 11. My daughter didn't start to eat ( ) I got home. 1 by 2 of 3 until 12.() she comes, the job will be 1 Until 2 In front of 4 neither finished. ) there is some snow. 3 how 4 which 4 who 4 that 4 since 4 during <新潟薬科大) BATT 3 Because of 4 By the time <近畿大) 105 〈昭和大〉 105 <法政大) 107 < 東京理科大 〉 107 < 広島修道大 > 108 〈立正大〉 108 <中京大 10 <大阪商業大 <新潟薬科

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英語 高校生

オレンジの線が引かれてるところの文構造がわかりません。文構造の解説をしてほしいです🙇🏻‍♀️🙇🏻‍♀️

5 Many linguists predict that at least half of the world's 6,000 or so languages will be 1-11 デッド dead or dying by the year 2050. Languages are becoming extinct at twice the rate of endangered mammals and four times the rate of endangered birds. If this trend 20 continues, the world of the future could be dominated by a dozen or fewer languages. Even higher rates of linguistic devastation are possible. Michael Krauss, director of 1-12 ディバステーション the Alaska Native Language Center, suggests that as many as 90 percent of languages could become moribund or extinct by 2100. According to Krauss, 20 percent to 40 percent of languages are already moribund, and only 5 percent to 10 percent are "safe" in the sense of being widely spoken or having official status. If people "become wise 10 and turn it around," Krauss says, the number of dead or dying languages could be more like 50 percent by 2100 and that's the best-case scenario. The definition of a healthy language is one that acquires new speakers, No matter 1-13 how many adults use the language, if it isn't passed to the next generation, its fate is already sealed. Although a language may continue to exist for a long time as a second 15 or ceremonial language, it is moribund as soon as children stop learning it. For example, out of twenty native Alaskan languages, only two are still being learned by children. Although language extinction is sad for the people involved,) why should the rest of us care? What effect will other people's language loss have on the future of people who speak English, for example? (A)Replacing à minor language with a more widespread one may even seem like a good thing, allowing people to communicate with each other more easily. But language diversity is as important as biological diversity. Andrew Woodfield, director of the Centre for Theories of Language and Learning 1-14 in Bristol, England, suggested in a 1995 seminar on language conservation that people do not yet know all the ways in which linguistic diversity is important. "The fact is, no s one knows exactly what riches are hidden inside the less-studied languages," he says. Woodfield compares one argument for conserving unstudied endangered plants (that they may be medically valuable with the argument for conserving endangered languages. "We have inductive evidence based on past studies of well-known languages that there will be riches, even though we do not know what they will be. (B) It seems paradoxical but it's true. By allowing languages to die out, the human race is destroying things it doesn't understand," he argues. Stephen Wurm, in his introduction to the Atlas of the World's Languages in Danger 1-

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