相信许多留学生对数学代考都不陌生,国外许多大学都引进了网课的学习模式。网课学业有利有弊,学生不需要到固定的教室学习,只需要登录相应的网站研讨线上课程即可。但也正是其便利性,线上课程的数量往往比正常课程多得多。留学生课业深重,时刻名贵,既要学习知识,又要结束多种类型的课堂作业,physics作业代写,物理代写,论文写作等;网课考试很大程度增加了他们的负担。所以,您要是有这方面的困扰,不要犹疑,订购myassignments-help代考渠道的数学代考服务,价格合理,给你前所未有的学习体会。

我们的数学代考服务适用于那些对课程结束没有掌握,或许没有满足的时刻结束网课的同学。高度匹配专业科目,按需结束您的网课考试、数学代写需求。担保买卖支持,100%退款保证,免费赠送Turnitin检测报告。myassignments-help的Math作业代写服务,是你留学路上忠实可靠的小帮手!


物理代写|电磁学代写electromagnetism代考|Parallel-Plate Capacitors

Now, let us consider a capacitor composed of two parallel conductor plates of equal area $A$, which are at a distance $d$, see also Fig.4.3. One of the plates carries a charge $+Q$, and the other $-Q$. Note that charges of like sign repel one another and that charges of opposite signs attract one another (see also Chap. 1). As a battery is charging a capacitor, electrons flow into the negative plate and out of the positive plate (see Fig. 4.2).

Note that the electric field between the plates of a parallel-plate capacitor is uniform near the center but nonuniform near the edges. When the capacitor plates are large, the accumulated charges can distribute themselves over a substantial area, and hence the amount of charge stored on each plate $Q$, for a given potential difference $\Delta V$, increases as the plate area increases to ensure a constant surface charge density $\sigma$. A simple argument can be used for that: because the electric field just outside the conductor is perpendicular to the surface of the conductor and with magnitude $E=\sigma / \epsilon_0$, where $E$ is proportional to constant $\Delta V$, then $\sigma$ is constant. Thus, we expect the capacitance $C$ to be proportional to the plate area $A$.

Above we derived a relationship between the electric field between the plates and magnitude of potential difference, given as
$$
E=\frac{\Delta V}{d}
$$
From Eq. (4.9), we see that when $d$ decreases, $E$ increases, for fixed $\Delta V$. If we move the plates closer together (that is, $d$ decreases), We also consider the situation before the charges have moved in response to that change, such that no charges have moved. Hence, the electric field between the plates is the same but extends over a shorter distance between plates. That situation corresponds to a new capacitor with a potential difference between the plates that is different from the terminal voltage of the battery. Now, across the wires connecting the battery to the capacitor exists a potential difference (see also Fig. $4.2$ for an illustration).

Based on the arguments that we discussed for a situation in Fig. 4.2, that potential difference creates an electric field in the wires that drives more charges onto the plates, which in turn increases the potential difference between the plates of the capacitor. When it becomes equal to the potential difference between the terminals of the battery.

物理代写|电磁学代写electromagnetism代考|Parallel Combination

Figure $4.5$ presents a combination of two capacitors connected in parallel. Also, we show a circuit diagram for this combination of capacitors, as often seen in an electric circuit. Note from Fig. $4.5$ that the left plates of the capacitors connect to the positive terminal of the battery using conducting wires; therefore, those plates, after equilibrium of the electric potential establishes, are at the same electric potential as the positive terminal of the battery. For the same reason, the right plate connecting to the negative terminal of the battery has equal electric potential with the negative terminal after the equilibrium of the electric potential establishes. As a result, the potential differences across each capacitor connected in parallel are the same and equal to the voltage applied to the battery; that is, $\Delta V_1=\Delta V_2=\Delta V$.

Applying the model described above in Fig. 4.2, when two capacitors are initially connected in a circuit, as shown in Fig. 4.5, electrons migrate between the wires and the plates. As a result, the left plates charge positively, and the right plates

negatively. In other words, the internal chemical energy stored in the battery is the source of that migration; that is, the internal chemical energy of the battery converts into electric potential energy associated with the surface charges in the plates of the capacitors at a separation $d$. During the process of the electrons migration, the voltage across the capacitors becomes equal to that across the battery terminals and then charge transfer stops. When that establishes in the circuit, the capacitors load to their maximum charge capacity.

In the following, we show a few steps to calculate the equivalent capacitance, $C_{e q}$, of the combinations of $C_1$ and $C_2$. For that, we denote by $Q_1$ and $Q_2$ the maximum charges on each capacitor, respectively, and by $Q$ the total charge stored by the two capacitors:
$$
Q=Q_1+Q_2
$$
$Q$ is also the charge stored in the capacitor $C_{e q}$. The voltages applied across each capacitor are the same, see also Fig. 4.5, and hence the charges in each capacitor are
$$
\begin{aligned}
&Q_1=C_1 \Delta V \
&Q_2=C_2 \Delta V
\end{aligned}
$$

物理代写|电磁学代写electromagnetism代考|PHY53040

电磁学代考

物理代写|电磁学代写electromagnetism代考|Parallel-Plate Capacitors

现在,让我们考虑一个由两块面积相等的平行导体板组成的电容器,它们之间的距离为$d$,也见图4.3。其中一块板带有$+Q$的电荷,另一块板带有$Q$的电荷。请注意,相同符号的电荷会相互排斥,相反符号的电荷会相互吸引(也见第1章)。当电池对电容器充电时,电子流入负极板,并从正极板流出(见图4.2)。

请注意,平行板电容器的板间电场在中心附近是均匀的,但在边缘附近是不均匀的。当电容器板块较大时,累积的电荷可以分布在相当大的面积上,因此在给定的电位差$Delta V$下,每个板块上储存的电荷量$Q$会随着板块面积的增加而增加,以确保表面电荷密度$sigma$不变。对此可以用一个简单的论证:因为导体外面的电场垂直于导体的表面,其大小为$E=/sigma/ epsilon_0$,其中$E$与常数$Delta V$成正比,那么$sigma$就是常数。因此,我们期望电容$C$与板面积$A$成正比。

以上我们得出了板块之间的电场和电位差大小之间的关系,给定为
$$
E=frac{Delta V}{d}。
$$
从公式(4.9)中,我们看到,当$d$减少时,$E$增加,对于固定的$Delta V$。如果我们将板块移近(即$d$减小),我们也考虑到电荷在响应该变化而移动之前的情况,如没有电荷移动。因此,板块之间的电场是相同的,但在板块之间延伸的距离更短。这种情况相当于一个新的电容器,板间的电位差与电池的端电压不同。现在,在连接电池和电容器的导线上存在着一个电位差(参见图4.2$的说明)。

根据我们在图4.2中讨论的论点,该电位差在导线中产生一个电场,促使更多的电荷进入极板,这反过来又增加了电容器极板间的电位差。当它变得与电池两端的电位差相等时。

物理代写|电磁学代写electromagnetism代考|Parallel Combination

图4.5$展示了两个电容器并联的组合。同时,我们还展示了这种电容器组合的电路图,这在电路中经常见到。从图4.5中注意到,电容器的左侧板用导电线连接到电池的正极;因此,这些板在电动势平衡建立后,与电池的正极处于相同的电动势。出于同样的原因,连接到电池负极的右板在电势平衡建立后与负极的电势相等。因此,并联的每个电容器上的电位差是相同的,并且等于施加在电池上的电压;也就是说,$/Delta V_1=/Delta V_2=/Delta V$。

应用上述图4.2的模型,当两个电容器最初连接在一个电路中时,如图4.5所示,电子在导线和板之间迁移。结果是,左边的板子会充以正电,而右边的板子会充以负电。换句话说,储存在电池中的内部化学能是这种迁移的来源;也就是说,电池的内部化学能转化为与电容器板中的表面电荷有关的电势能,其间隔为$d$。在电子迁移的过程中,电容器两端的电压变得与电池两端的电压相等,然后电荷转移停止。当电路中出现这种情况时,电容器就会加载到其最大充电能力。

在下文中,我们将展示几个步骤来计算$C_{e q}$的等效电容,$C_1$和$C_2$的组合。为此,我们用$Q_1$和$Q_2$分别表示每个电容器上的最大电荷,而用$Q$表示两个电容器储存的总电荷。
$$
Q=Q_1+Q_2
$$
$Q$也是存储在电容器$C_{e q}$中的电荷。施加在每个电容器上的电压是相同的,也见图4.5,因此每个电容器中的电荷是
$$
\begin{aligned}
&Q_1=C_1 δ V\\
&Q_2=C_2 δV
\end{aligned}
$$

物理代写|电磁学代写electromagnetism代考

myassignments-help数学代考价格说明

1、客户需提供物理代考的网址,相关账户,以及课程名称,Textbook等相关资料~客服会根据作业数量和持续时间给您定价~使收费透明,让您清楚的知道您的钱花在什么地方。

2、数学代写一般每篇报价约为600—1000rmb,费用根据持续时间、周作业量、成绩要求有所浮动(持续时间越长约便宜、周作业量越多约贵、成绩要求越高越贵),报价后价格觉得合适,可以先付一周的款,我们帮你试做,满意后再继续,遇到Fail全额退款。

3、myassignments-help公司所有MATH作业代写服务支持付半款,全款,周付款,周付款一方面方便大家查阅自己的分数,一方面也方便大家资金周转,注意:每周固定周一时先预付下周的定金,不付定金不予继续做。物理代写一次性付清打9.5折。

Math作业代写、数学代写常见问题

留学生代写覆盖学科?

代写学科覆盖Math数学,经济代写,金融,计算机,生物信息,统计Statistics,Financial Engineering,Mathematical Finance,Quantitative Finance,Management Information Systems,Business Analytics,Data Science等。代写编程语言包括Python代写、Physics作业代写、物理代写、R语言代写、R代写、Matlab代写、C++代做、Java代做等。

数学作业代写会暴露客户的私密信息吗?

我们myassignments-help为了客户的信息泄露,采用的软件都是专业的防追踪的软件,保证安全隐私,绝对保密。您在我们平台订购的任何网课服务以及相关收费标准,都是公开透明,不存在任何针对性收费及差异化服务,我们随时欢迎选购的留学生朋友监督我们的服务,提出Math作业代写、数学代写修改建议。我们保障每一位客户的隐私安全。

留学生代写提供什么服务?

我们提供英语国家如美国、加拿大、英国、澳洲、新西兰、新加坡等华人留学生论文作业代写、物理代写、essay润色精修、课业辅导及网课代修代写、Quiz,Exam协助、期刊论文发表等学术服务,myassignments-help拥有的专业Math作业代写写手皆是精英学识修为精湛;实战经验丰富的学哥学姐!为你解决一切学术烦恼!

物理代考靠谱吗?

靠谱的数学代考听起来简单,但实际上不好甄别。我们能做到的靠谱,是把客户的网课当成自己的网课;把客户的作业当成自己的作业;并将这样的理念传达到全职写手和freelancer的日常培养中,坚决辞退糊弄、不守时、抄袭的写手!这就是我们要做的靠谱!

数学代考下单流程

提早与客服交流,处理你心中的顾虑。操作下单,上传你的数学代考/论文代写要求。专家结束论文,准时交给,在此过程中可与专家随时交流。后续互动批改

付款操作:我们数学代考服务正常多种支付方法,包含paypal,visa,mastercard,支付宝,union pay。下单后与专家直接互动。

售后服务:论文结束后保证完美经过turnitin查看,在线客服全天候在线为您服务。如果你觉得有需求批改的当地能够免费批改,直至您对论文满意为止。如果上交给教师后有需求批改的当地,只需求告诉您的批改要求或教师的comments,专家会据此批改。

保密服务:不需求提供真实的数学代考名字和电话号码,请提供其他牢靠的联系方法。我们有自己的工作准则,不会泄露您的个人信息。

myassignments-help擅长领域包含但不是全部:

myassignments-help服务请添加我们官网的客服或者微信/QQ,我们的服务覆盖:Assignment代写、Business商科代写、CS代考、Economics经济学代写、Essay代写、Finance金融代写、Math数学代写、report代写、R语言代考、Statistics统计学代写、物理代考、作业代写、加拿大代考、加拿大统计代写、北美代写、北美作业代写、北美统计代考、商科Essay代写、商科代考、数学代考、数学代写、数学作业代写、physics作业代写、物理代写、数据分析代写、新西兰代写、澳洲Essay代写、澳洲代写、澳洲作业代写、澳洲统计代写、澳洲金融代写、留学生课业指导、经济代写、统计代写、统计作业代写、美国Essay代写、美国代考、美国数学代写、美国统计代写、英国Essay代写、英国代考、英国作业代写、英国数学代写、英国统计代写、英国金融代写、论文代写、金融代考、金融作业代写。