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自然科學
大學

問16 18

兩。人修飾柳「短量」交3 量極要 全 “bel》 以外叻原子在生物髓代W 過 Ba 芒元素 可罰用作由時 的蘊莽量極微 聽的段類存活人大記用 數回來表未"緒方說、,:- (146) 原子的反應性源自 闌 共計二 最外面戰道電子層與原子核的平均啞站 B. 價層中未配對電子的存在 tial energies ) 的總和 C. 所有電子層之位能 (poten! D. 價層的位能 2 s和p軌域間的和能差 達到平衡的化學反應。 7 直列哪一敘述正確描述任何已 A. 產物的濃度與反應物的濃度相等 B. 順向反應與逆向反應的速率相等 C. 順向反應與逆向反應皆已停頓 D. 反應已走到不可逆的地縣 E. 反應物已消耗綴盡 三8 分子的形狀: A. 部分視軌域形狀而定 B. 影響它們的生物功能 C. 視陰電性而定 D. 視元素週期表的位置而定
自然科學
大學

想問一下48跟49用克希荷夫要怎麼解qq 感謝各位了

同點 上 崗 |倍全 problem 45 上 FIGURE25,29 ) the Current 8UDP 25.30,. find (4 () res1stOT 46. ln the Circuit 01 Fig, <- Tent througl the 6 battery and (b) the eu! 10 和aa 6V竹 FIGURE25.30 Problems 46 and 47 e2-0 reslstor? ris dissipated in th 2 47. In Fig. 25.30, how much powe 48.“What's the ammeter reading in Fig. FIGURE25.31 Problem 48 In Fig. 25.32,和有 i i 晤 ind the equivalent reSlStance meaSured betweenA 及 2人 2 有 7 FIGURE25,32 Problem 49 50. Find a 1 three currents in the circui 1 W t ITcuilt 01 Fig. 25.13 with the values 2 le Vo]tage acro, 6 92U- 上 人 Ih ge acrosS the 30-k(0) resistor 1 1g. 25.33 isS measured 上 meter, (b) a350-k0 財 d (c) a With (3) a 150-k 0 Volt anhd ( ) : 50-MOQ digi gltal m' 人2 eter. What does each read, to two Si Slgnitilcamt
自然科學
大學

想問RC circuit 中 charge 跟 discharge 如附圖內的等式是怎麼得出的呢? 思考了一段時間也上網查過了

The sum ofthe potential difference across the capacitor and resistoris away Constant, so Vc 十 MRg 三委. As charge flows to the Capacitor, the potential difer: ence across it increases, which means that the Potential difference across及誠 the current through the circuit, must decrease. In this circuit, the current /當 Credyey the charge on the capacitor, and therefore 7 二 十ZO/2/. As the currit decreases, we expect the Tate at which the capacitor charges also to decrease When the potential difference across C Teaches 儿, the potential difference acr0S AR 1s zero: The current Stops flowing, and the charge on the capacitor ha5出 maximum value Oo = Cx, When 7 = +Z0/dr is used in the loop rule, we find
自然科學
大學

求解圖裡UICK quiz的第二小題

acit0r 1taneOuls CUrTent Differentiating Equation 27.22 with respectto time gives the inst: as afunction of time: 4 tt號 一Fe ptasafurc 主二 where Q;/有CC 三方 is the initial current. Figure 27.15b 5 in the resistor that we guessedin order to-apply Kirch Equations 27.15 and 27.21. Equation 27.23 shows that the ci ing capacitor is negative, indicating that the current 1s Figure 27.15c. Both the charge on the capacitor and the ct tially at a rate characterized by the time'constant7了三用C. 人 i 一 GOuicK ouiz 27.5 Considerthe circuitin Figure 27.17 and assume the battery has after the switch is closed, what is the currentin the Figure 27.17 no internal resistance. () 」 battery (a) 0 (b) &/2A(G 28/Z04 8/元(e) impossible to determine (ii) After a 有 eyerylong time, what is the Currentin the battery? Choose from the same choices. theswitch is CC (3 前:銜1加信介2放 IntermittentWindshield Wipers nobiles are equipped with windshield wipers that can operate intermittently during alight rainfall. How does ofsuch wipers depend on the charging and discharging ofacapacitor7 民 The wipers are part ofan 及C circuit whose time constant can be varied by selecting different values of及through amultipo- Sition sWitch. As the voltage across the capacitor increases, the capacitor reaches a point at which it discharges and Higgers the wipers. The circuit then begins another charging cycle. The time interval between the individual sweeps of the wiperS 1 determinedjby the value ofthe time constant.
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