欧姆法律与基尔乔夫法律之间的区别

关键区别 - 欧姆法律与基希霍夫定律

When it comes to understanding theelectricity，了解原始参数之间的关系非常重要，voltage and current。描述这种关系的基本原则是欧姆的定律。另一方面，基希霍夫定律是一种分别描述这些参数的属性的理论。因此，欧姆定律和基尔乔夫定律之间的关键区别在于欧姆的定律描述了电阻元素的电压与电流之间的关系，而基希霍夫（Kirchhoff）’s law describes the behaviour of current and voltage in a circuit branch.

内容

1.Overview and Key Difference
2.What is Ohm’s Law
3.What is Kirchhoff’s Law
4.并排比较 - 欧姆法律与基希霍夫法律的表格形式
5.概括

欧姆的定律是什么？

Ohm’s Law states that the current flowing through aconductoris proportional to the voltage across it and vice versa. This principle was founded by the German physicist Georg Ohm and is given by,

v = ir

可以将欧姆定律与管道中的水流进行比较。两端之间的电势差使水通过管道像电流一样，这是由电阻元件上的电压差驱动的。此外，增加电流的降低电阻等同于管道的横截面区域减少，从而减少了水流。

With regard to a single equipment or a circuit of elements as a whole, Ohm’s Law is used to calculate the total resistance across the element or the circuit, with the measured current and the voltage. With the calculated resistance, the power consumption of the circuit could be determined or predicted if the resistance value is changed by any mean such as temperature.

The complex form of Ohm’s Law is applicable to AC circuits where V and I are complex variables. In that case, R refers to theimpedance电路（z）的。阻抗也是一个复杂的数字，其中只有实际部分有助于主动功率耗散。

What is Kirchhoff’s Law?

基希霍夫的法律是由德国物理学家古斯塔夫·基希霍夫（Gustav Kirchhoff）提出的。基希霍夫的法律有两种形式：基希霍夫现行法律（KCL）和基尔乔夫的电压法（KVL）。KCL和KVL分别描述了当前流量和电压的保护。

基尔乔夫现行法律(KCL)

KCL指出进入节点的总电流（几个分支电路的连接点），从节点流出的总电流相等。

Kirchhoff’s Voltage Law (KVL)

KLV, on the other hand, states that the sum of voltages across a closed loop is zero.

这是另一种形式表示的，因为电路的两个节点之间的电压之和等于这两个节点之间的每个分支电路。可以如下图所示。

Here,

v₁+ v₂+ v₃- v₄= 0

KVL and KVC are extremely useful in circuit analysis. However, Ohm’s Law must be used together with them in solving circuit parameters. For example of such a circuit analysis, the flowing figure is given.

Considering the nodes A and B, KCL can be applied as follows.

For node A; I₁+ I₂= I₃

对于节点B;我₁+ I₂= I₃

然后将KVL应用于闭环（1）

V₁+ I₁R₁+ I₃R_{3 =}0

Then KVL is applied to the closed loop (2)

V₂+ I₂R₂+ I₃R_{3 =}0

然后将KVL应用于闭环（3）

V₁+ I₁R₁– I₂R₂- v_{2 =}0

By solving above equations any unknown parameter of the circuit can be found. Note that, Ohm’s Law is used when determining the voltages across the resistors.

What is the Difference Between Ohm’s Law and Kirchhoff’s Law?

欧姆法律与基尔乔夫法律
欧姆定律描述了电阻元素之间电压与电流之间的关系。	基尔乔夫定律分别描述了电路分支中电流和电压的行为。
Law
Ohm’s Law states that voltage across aconductoris proportional to the current flows through it.	KCL states that the sum of current flows to a node is equal to zero while KVL states that the sum of voltages in a closed loop is zero.
申请
Ohm’s Law is applicable to a single resistive element or set of resistive circuits as a whole.	KCL and KVL are applicable to a series of resistive elements in a circuit.

摘要 - 欧姆法律vs Kirchhoff法律

Ohm’s and Kirchhoff’s Laws are two fundamental theories in electrical circuit analysis. They describe the properties and relationship of voltage and current in a single conductive element and a branch of electrical circuit respectively. While Ohm’s Law is applicable to a resistive element, Kirchhoff’s Laws are applied to a series of elements. This is the most important difference between Ohm’s law and Kirchhoff’s law. KCL and KVL are usually used in circuit analysis together with Ohm’s Law.

Download PDF Version of Ohm’s Law vs Kirchhoff’s Law

You can download PDF version of this article and use it for offline purposes as per citation notes. Please download PDF version hereDifference Between Ohms Law and Kirchhoffs Law.

参考：

1. “Kirchhoffs Circuit Law.” Kirchhoffs Circuit Law,Available here。Accessed 4 Sept. 2017.
2. “Kirchhoff’s circuit laws.” Wikipedia, Wikimedia Foundation, 1 Sept. 2017,Available here。Accessed 4 Sept. 2017.

我mage Courtesy:

1. waveGuide2的“ ohmslaw”（talk）（转移bynk/最初由waveGuide2上传）（最初是在en.wikipedia上载于en.wikipedia）（公共域）（通过Commons Wikimedia
2. “Kirchhoff’s Current Law” By inductiveload – Own drawing (Public Domain) viaCommons Wikimedia
3. “Kirchhoff voltage law” By Kwinkunks – Own work(CC BY-SA 3.0)viaCommons Wikimedia