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

Prawo napięcia Kirchhoffa, czyli KVL, opiera się na zasadzie zachowania energii.
Stwierdza, że suma algebraiczna wszystkich napięć wokół zamkniętej ścieżki lub pętli w obwodzie wynosi zero.
Kierunek pętli wokół obwodu może być zgodny z ruchem wskazówek zegara lub przeciwny do ruchu wskazówek zegara i może zaczynać się z dowolnego miejsca.
Po wybraniu kierunku pętli, napięcia dodatnie mają najpierw napotkany biegun ujemny, a napięcia ujemne mają najpierw napotkany biegun dodatni.
Zastosowanie KVL do każdej pętli i przegrupowanie warunków daje jego alternatywną formę, która mówi, że suma spadku napięcia jest równa sumie dostarczonych napięć.
Weźmy na przykład lampki choinkowe, w których trzy lampki LED połączone szeregowo są ze sobą połączone.
Jeśli każde światło wymaga trzech woltów do włączenia, napięcie potrzebne do zasilania akumulatora do zasilania tych świateł jest określane przez zastosowanie KVL.
Napięcie akumulatora jest równe sumie spadku napięcia na trzech światłach.

napięciowe prawo kirchhoffa

Napięciowe prawo Kirchhoffa (KVL, z ang. Kirchhoff's Voltage Law) to kolejna podstawowa zasada w elektrotechnice, wprowadzona przez fizyka Gustava Roberta Kirchhoffa. Prawo to opiera się na zasadzie zachowania energii, która stwierdza, że energii nie można ani wytworzyć, ani zniszczyć, a jedynie przenieść lub przekształcić z jednej formy w drugą.

KVL stwierdza, że algebraiczna suma wszystkich napięć wokół zamkniętej ścieżki lub pętli w obwodzie wynosi zero. Oznacza to, że całkowite napięcie dostarczane w pętli jest równe całkowitemu spadkowi napięcia na elementach tej pętli.

Kierunek pętli wokół obwodu może być zgodny z ruchem wskazówek zegara lub przeciwny do ruchu wskazówek zegara i może zaczynać się od dowolnego punktu. Po wybraniu kierunku pętli, napięcia dodatnie to te, w których najpierw napotkany jest zacisk ujemny, a napięcia ujemne to te, w których najpierw napotkany jest zacisk dodatni.

Stosując KVL w kierunku zgodnym z ruchem wskazówek zegara i zmieniając warunki, można uzyskać alternatywną formę tego prawa: suma spadków napięcia na elementach pętli jest równa sumie dostarczonych napięć.

Rozważmy na przykład domowy system oświetlenia, w którym połączone są szeregowo trzy diody LED. Każde światło wymaga trzech woltów do włączenia. Stosując KVL, możemy określić napięcie potrzebne akumulatorowi do zasilania tych świateł. Napięcie akumulatora jest równe sumie spadków napięcia na trzech lampach, która wynosi dziewięć woltów.

Aby jednak KVL było prawdziwe, musi zostać spełniony kluczowy warunek: obwód nie może zawierać dwóch różnych napięć połączonych równolegle, chyba że są one równe. Dzieje się tak dlatego, że w połączeniu równoległym do wszystkich komponentów przykładane jest to samo napięcie, a jakakolwiek rozbieżność naruszałaby prawo zachowania energii.

Napięciowe prawo Kirchhoffa

Prawo napięcia Kirchhoffa, czyli KVL, opiera się na zasadzie zachowania energii.
Stwierdza on, że algebraiczna suma wszystkich napięć wokół domkniętego ...

Education

JoVE Core

Electrical Engineering

Elektrotechnika

Unit 1

Jednostka 1

Basics of Electric Circuits

Podstawy obwodów elektrycznych

KEY TERMS AND CONCEPTS

KLUCZOWE POJĘCIA I KONCEPCJE

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

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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,...

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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.

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Voltage Balance in Closed Circuit Loops

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