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物理 高校生

啓林館 物理基礎 改訂版 静電気と電流の章末問題です。解説が載ってなくて、困ってます。解説してくれる方がいましたらお願いします

抗値はそれぞれいくらか。ただし、電流計に の抵抗と 6.0 Vの電池に接続したところ, 電 うに, A, Bを並列接続したものを、 1.3Ω (2) Pで消費される電力のうち, 70%が水を2.5m 図のように,電圧 100 V の電源を抵抗Rとポンプ Pに接続する。Rの抵抗値が15Ωのとき, 電圧計の かかる電圧は無視できるものとする。 にかかる電圧は無視できるものとして, 次の問いに答 読みが 70 V であった。電圧計に流れる電流や電流計 の抵抗の接続 1 一様な2本の金属棒 A, Bがある。 の材質は同じた: Aの断面積はBの 1 倍である。図のょ A, p.180, 182, 183 3 流計には 1.5 A の電流が流れた。 A, B の B 6.0V 1.30 の電力とジュール熱 p.185例題1 R えよ。 電流計に流れる電流の強さを求めよ。 100 V 15 の高さにくみ上げる仕事に使われた。Pが1.0分間 にくみ上げる水の質量を求めよ。ただし,重力加速度の大きさを9.8m/s°とする。 13) Rで1分間に発生するジュール熱を求めよ。 3自由電子の動きとオームの法則 川を流れる水の速さは複雑な要因によって決まるが, おお b p.178~180や 20 むね川の傾き(図Aの一に比例するものとする。電流を担 ; う自由電子の場合も同穏だと考えると, 図Bのように長さL の導体に電圧Vをかけた場合,川のモデルでいう川の傾き そに祖当すると考えてよい。よって, 自由 V は,図Bでは O図A a V と 電子が移動する速さひは,比例定数をんとして,ひ=k 表されることになる。自由電子の電気量の絶対値を e, 導体 の単位体積あたりの自由電子の個数をn, 導体の断面積をS として,次の問いに答えよ。 25 Tトー O図B 第1章 静電気と電流 第1章

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数学 高校生

式と計算 この問題で、対称性を崩さないように①、➁、③の辺々を足しているのようなのですが、なぜ辺々を足すことができるのでしょうか?何となくそうなると言われればわかる気はしますが、納得しにくくて。どなたかわかる方いらっしゃいますか?

=k(キ0) が成り立つとき, kの値を求めよ 比例式の値 考え方 比例式は,「=k」とおく、 2(y+z)=kx, 2(z+x)=ky, 2(x+y)=kz から kom。 Check 例題 26 を満たすとき、 2(y+z)_ 2(z+x)_2(x+y) この女の様 y X x, 3, 2が を求めよ。 めればよい.また, xキ0, yキ0, zキ0 である。 2(x+y) 2(y+z)_ 2(z+x)_. y -=k とおくと, る 解答 a x 2(+a)=Dkx 2(z+x)=ky 2(x+y)=kz また,xキ0,_yキ0,zキ0 である。 の+2+3 より, 4(x+y+z)-k(x+y+z)=0 2) 3 b+ (分母)+0 各辺の辺々を加え。 移項して整理す。 x+y+z で両 割ってはいけな。 4(x+y+z)=k(x+y+z) だから, (x+y+z)(4-k)=0 x+y+z=0 または 4-k=0 y+z=-x したがって, (i)x+y+z=0のとき, これを①に代入して, xキ0 より, (i) 4-k=0 のとき, このとき, 0, 2, ③を解くと, これは,xキ0, yキ0, zキ0 を満たすすべての x, y, 2について成り立つ。 よって, (i), (i)より, 求める値は, とに注意 (式) (この段階では -2x=kx k=-2 x+y+z=0 k=4 の可能性がある x=y=z -2, 4 Focus +y+z など文字を含む式では割らずに因数分解 注) b 3ー&のとき, bx+qy+rzキ0 ならば, patqb+rC _1e であるこ a=kx, b=ky, c=kz を代入するとわかる.(加比の理,p.57練習 252参に このことを用いると, 例題26は次のように求めることもできる。 x y px+qy+rz x+y+zキ0 のとき, 2(y+z)+2(z+x)+2(x+y)_4(x+y+z)。 x+y+z k= x+y+z x+y+z=0 のとき, y+z=-x より, k=2(y+z)_ニ2x_-2 x x 東習 26 a+b b+c_c+a C a b y_y+z x- 2+7x 2 X

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英語 高校生

どなたか英語の得意な方この問題問いてくださいませんか、、 先日受験して不安で眠れません

6. 次の英文を読み, 以下の設問に答えよ。 legally as a *trophy. In 2003, a lone hunter killeda rhino on a legal safari in South Africa and brought it back to Asia. Dozens of poachers soon followed. The sound of rifles being fired could be heard in the dark forest just as each paying $50,000 for a hunt. It seems like a lot to pay, but poachers can Damien Mander arrived at his campfire after a long day training *game ranger make as much as $200,000 in profits by selling a pair of horns on *the black recruits in Zimbabwe's Nakavango *game reserve. "There, near the eastern market. boundary," he pointed. He and his rangers grabbed their guns, radios, and ull Many officials in Vietnam are fighting back against reports that the country medical kits. They then drove into the night, hoping to stop the shooter. is the main market for rhino horn, stating that rhino horn bound for Vietnam (21) And so goes a night on the front lines of southern Africa's ruthless * rhino is merely in transit for another country. Do Quang Tung, deputy director of war, which has seen more than a thousand rhinos killed since 2006. At the CITES Managing Authority in Vietnam, said the country "could not be the main bloody heart of this conflict is the rhino's horn, a prized ingredient in traditional market for South African rhino horn," claiming that the majority of Vietnamese Asian medicine. Prices range from $33 to $133 a gram, which at the top end is people would not be able to ( 26 ) rhino horn. Even if there is an emerging double the price of gold. group of people who can ( 26 ) it, he thinks it is too small to make the country Although the range of the two African species 一 the white rhino and its a significant consumer. Professor Dang Huy Huynh, chairman of the Vietnam smaller cousin, the black rhino- has been reduced primarily to southern Africa Zoological Society, says that rhino horn has never been a popular ingredient in and Kenya, their populations had shown signs of improvement. In 2007 white traditional medicine. rhinos numbered 17,470, while blacks had nearly doubled to 4,230 since the mid Recently, there has been a renewed interest in the unproven belief that rhino 90s. horn has healing power. For at least 2,000 years, Asian medicine has prescribed For conservationists these numbers represented a triumph. In the 1970s rhino horn to reduce fever and treat a range of illnesses, but the handful of 22 and '80s, *poaching had nearly caused the two species to become extinct. Ther studies which have been conducted on rhino horn have not found any proof that China banned rhino horn from traditional medicine, and Yemen forbade its ust it can reduce fever. The newest rumor is that it cures cancer, but doctors say in ceremonial knife handles. All signs pointed to better days. But in 2008 th the proof is nonexistent一 no research has been published on the horn's efficacy 23) number of poached rhinos in South Africa shot up to 83, from just 13 in 200' as a cancer treatment. But even if rhino horn is not an effective cure for anything, let alone cancer, that doesn't mean it has no effect, says Mary Hardy. By 2010 the figure had soared to 333, followed by over 400 in 2011. Most of th 27) medical director of Simms/Mann UCLA Center for Integrative Oncology. "Belief horn trade was found to lead to Southeast Asia. in a treatment, especially one that is wildly expensive and hard to get, can have *Javan rhinos once lived in Vietnam's forests. ( 24 ) It had a bullet a powerful effect on how a patient feels," she says. its leg and its horn had been removed. In any event, John Hume believes no rhinos need to die to supply the rhino Even with the rhinos gone, rhino horn can still be found in Vietnam. This 28 25 horn to those who want it. The 69-year-old * entrepreneur has acquired one of because South African law, which complies with the Convention on Internatio the largest privately-owned rhino herds in the world, and currently has more Trade in Endangered Species (CITES), allowS a rhino's horn to be expor ○M3(45)

解決済み 回答数: 1