Name: voltage balance in closed circuit loops
Uploaded: 2024-04-11T12:48:28.000Z
Duration: 1 min 4 s
Channel: JoVE

K12 Standards

Arizona Science Standards

High School

Physical Science

HS+Phy.P4

HS+Phy.P4U1.8

Kirchhoff's Voltage Law

Kirchhoff의 전압 법칙 또는 KVL은 에너지 보존 원칙을 기반으로 합니다.
회로 내의 닫힌 경로 또는 루프 주변의 모든 전압의 대수 합이 0임을 나타냅니다.
회로 주위의 루프 방향은 시계 방향 또는 시계 반대 방향일 수 있으며 어디에서나 시작할 수 있습니다.
루프 방향이 선택되면 양의 전압은 음의 단자를 먼저 만나고 음의 전압은 양의 단자를 먼저 만나게 됩니다.
각 루프에 KVL을 적용하고 항을 재정렬하면 전압 강하의 합이 공급 전압의 합과 같다는 대체 형식이 제공됩니다.
예를 들어, 직렬로 연결된 세 개의 LED 조명이 함께 연결된 크리스마스 트리 조명을 생각해 보십시오.
각 조명을 켜는 데 3볼트가 필요한 경우 배터리가 이러한 조명에 전원을 공급하는 데 필요한 전압은 KVL을 적용하여 결정됩니다.
배터리 전압은 세 개의 표시등에서 전압 강하의 합과 같습니다.

키르히호프의 전압 법칙

키르히호프의 전압 법칙(KVL)은 물리학자 구스타프 로버트 키르히호프(Gustav Robert Kirchhoff)가 소개한 전기 공학의 또 다른 기본 원리입니다. 이 법칙은 에너지 보존의 원리에 뿌리를 두고 있는데, 에너지는 생성되거나 파괴될 수 없으며, 단지 한 형태에서 다른 형태로 전달되거나 변환될 뿐이라는 것입니다.

KVL은 회로 내 폐쇄 경로 또는 루프 주변의 모든 전압의 대수적 합이 0이라고 명시합니다. 이는 루프에 공급된 총 전압이 해당 루프의 구성 요소에 걸친 총 전압 강하와 동일하다는 것을 의미합니다.

회로 주변의 루프 방향은 시계 방향 또는 시계 반대 방향일 수 있으며 어느 지점에서나 시작할 수 있습니다. 루프 방향이 선택되면 양의 전압은 음의 단자가 먼저 만나는 전압이고, 음의 전압은 양의 단자가 먼저 만나는 전압입니다.

KVL을 시계 방향으로 적용하고 항을 재배열하면 법칙의 대체 형태가 있습니다. 즉, 루프의 구성 요소 전체에 걸친 전압 강하의 합은 공급된 전압의 합과 같습니다.

예를 들어 직렬로 연결된 3개의 LED 조명이 함께 연결된 가정용 조명 시스템을 생각해 보세요. 각 조명을 켜려면 3볼트가 필요합니다. KVL을 적용함으로써 배터리가 이러한 조명에 전력을 공급하는 데 필요한 전압을 결정할 수 있습니다. 배터리 전압은 3개의 조명에 걸리는 전압 강하의 합인 9V와 같습니다.

그러나 KVL이 성립하려면 중요한 조건이 충족되어야 합니다. 즉, 회로는 동일하지 않은 두 개의 서로 다른 전압을 병렬로 포함할 수 없습니다. 병렬 연결에서는 모든 구성 요소에 동일한 전압이 적용되며 불일치가 발생하면 에너지 보존 법칙에 위배되기 때문입니다.

Kirchhoff의 전압 법칙 또는 KVL은 에너지 보존 원칙을 기반으로 합니다.
그것은 닫힌 주변의 모든 전압의 대수 합이 ...

Education

교육

JoVE Core

Electrical Engineering

전기공학

Unit 1

제1단원

Basics of Electric Circuits

전기 회로의 기초

KEY TERMS AND CONCEPTS

주요 용어 및 개념

voltage balance in closed circuit loops

Kirchhoff's Voltage Law explains how voltage is balanced in a closed circuit loop. It is a basic rule in electrical engineering and comes from the idea of energy conservation. Energy can change form, but it cannot be created or destroyed.

KVL states that the algebraic sum of all voltages around a closed path, or loop, is zero. In other words, the total voltage supplied in a loop equals the total voltage drop across the components in that loop. A loop can be traced clockwise or anticlockwise, and it can begin at any point.

The direction of the loop matters when you assign signs to voltages. If you meet the negative terminal first, the voltage is positive. If you meet the positive terminal first, the voltage is negative. When KVL is written in the clockwise direction and the terms are rearranged, the law can also be stated as the sum of voltage drops in a loop equals the sum of supplied voltages.

A simple household lighting example shows how KVL works. Three LED lights connected in series, with each light needing three volts, require a nine-volt battery to power them. The battery voltage matches the sum of the voltage drops across the three lights.

KVL also depends on an important circuit condition. A circuit cannot contain two different voltages in parallel unless those voltages are equal. In parallel connections, the same voltage appears across each component. If the voltages were different, the circuit would break the rule of energy conservation.

Voltage Balance in Closed Circuit Loops

charge and current

Electric Charge in Circuits

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voltage

Voltage in Electric Circuits

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power and energy

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electric circuit elements

Circuit Elements: Passive, Active, and Linear

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circuit terminology

Circuit Parts: Branches, Nodes, and Loops

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independent and dependent sources

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ohm's law

Resistance and Conductance in Circuits

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kirchhoff's current law

Kirchhoff's Current Law at Circuit Nodes

Kirchhoff's Current Law explains how current behaves at a circuit node. A node is the point where two or more circuit elements meet. The law says the current entering a node equals the current leaving it. That balance follows the rule of charge conservation, which means electric charge is not lost at the junction. When applying KCL, currents entering the node are treated as positive and currents leaving the node are treated as negative. The currents can be added algebraically at the node, and...

kirchhoff's voltage law

Kirchhoff's Voltage Law explains how voltage is balanced in a closed circuit loop. It is a basic rule in electrical engineering and comes from the idea of energy conservation. Energy can change form, but it cannot be created or destroyed. KVL states that the algebraic sum of all voltages around a closed path, or loop, is zero. In other words, the total voltage supplied in a loop equals the total voltage drop across the components in that loop. A loop can be traced clockwise or anticlockwise,...

voltage dividers

Series Resistors and Voltage Split

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current dividers

Parallel Resistors and Current Division

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design example: resistive touchscreen

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A resistive touchscreen uses voltage mapping to locate a finger touch on a mobile device. It is built from two metallic layers. The top layer is flexible, and the bottom layer is rigid. A narrow gap separates them, and the high resistance between the layers is an important part of the design. When a user touches the screen, the two layers meet at one point. That contact point is called the touchpoint. The touch lowers the resistance between the layers at that spot and changes the electrical...

key terms and concepts

Learn how Kirchhoff's Voltage Law balances voltage in a closed loop, how to assign signs, and why a series LED example needs a 9-volt battery.

Voltage Balance in Closed Circuit Loops | JoVE K12

JoVE Core Electrical Engineering offers easy-to-understand animated videos that cover fundamental concepts of electric circuits along with circuit analysis techniques. It incorporates first-order and second-order circuits using operational amplifiers and circuit transformation concepts. The inclusion of practical design examples and real-world applications through scientist-in-action videos adds significant educational value, making complex concepts accessible.

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Voltage Balance in Closed Circuit Loops

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