Name: circuit elements: passive, active, and linear
Uploaded: 2024-04-11T12:48:28.000Z
Duration: 1 min 21 s
Channel: JoVE

Os elementos do circuito são os blocos de construção básicos de um circuito elétrico. Eles podem ser categorizados como elementos ativos e passivos.
Os elementos ativos podem gerar energia, enquanto os elementos passivos absorvem energia.
Exemplos de elementos ativos incluem fontes de tensão ou corrente, enquanto resistores, capacitores e indutores são exemplos de elementos passivos.
Os elementos do circuito podem ser classificados como lineares ou não lineares.
Um circuito ou um elemento é considerado linear se a excitação e a resposta do elemento seguirem os princípios de superposição e homogeneidade.
Suponha que uma tensão v1 leve a uma resposta i1 e uma tensão v2 leve a uma resposta i2. Se o elemento responde à soma das tensões com a soma das respostas, então ele satisfaz o princípio da superposição.
Além disso, a propriedade de homogeneidade é satisfeita quando a multiplicação da entrada de um dispositivo linear por qualquer constante resulta em uma multiplicação equivalente da saída.
Elementos lineares como resistores, capacitores e indutores exibem características lineares.
Elementos como termistores não são lineares, pois não cumprem esses princípios.

elementos do circuito elétrico

Electric Circuit Elements

Elementos de circuito são componentes fundamentais de um circuito elétrico, formando a base de sua estrutura. Essencialmente, um circuito elétrico é a interligação desses elementos. Dentro dos circuitos elétricos podemos encontrar dois tipos de elementos: passivos e ativos. Os elementos ativos têm a capacidade de gerar energia, enquanto os elementos passivos não. Os elementos passivos incluem componentes como resistores, capacitores e indutores, enquanto os elementos ativos normalmente abrangem geradores, baterias e amplificadores operacionais.

Os elementos ativos mais importantes são fontes de tensão ou corrente, que geralmente fornecem energia ao circuito conectado. Existem inúmeras maneiras de categorizar os elementos do circuito. Por exemplo, distinguir modelos lineares de modelos não lineares é crucial porque circuitos compostos inteiramente por elementos de circuito linear são mais simples de analisar do que aqueles com alguns elementos não lineares.

Um elemento ou circuito é considerado linear se a excitação e a resposta do elemento atenderem a certas condições. Ambas as propriedades de superposição e homogeneidade são atendida por um elemento linear. Considere um cenário onde a excitação é a corrente (i) e a resposta é a tensão (v). Se o elemento estiver sujeito a uma corrente (i1), ele fornece uma resposta (v1). Da mesma forma, quando o elemento é exposto a outra corrente (i2), ele provoca uma resposta (v2).

Qualquer elemento do circuito que não atenda ao princípio de superposição ou de homogeneidade é classificado como não linear. Os termistores são exemplos de tais elementos não lineares.

Elementos do circuito elétrico

Os elementos do circuito são os blocos de construção básicos de um circuito elétrico. Eles podem ser categorizados como elementos ativos e passivos.
Os elementos ativos podem ...

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JoVE Core

Electrical Engineering

Unit 1

Basics of Electric Circuits

KEY TERMS AND CONCEPTS

circuit elements: passive, active, and linear

Circuit elements are the building blocks of an electric circuit. An electric circuit is the connection of these elements. In this context, circuit elements are often grouped by how they behave and whether they supply energy.

One major group is passive elements. These elements do not generate energy. Common passive elements include resistors, capacitors, and inductors. The other group is active elements, which can generate energy. Generators, batteries, and operational amplifiers are typical active elements, and voltage or current sources are especially important because they usually provide power to the connected circuit.

Circuit elements can also be sorted as linear or nonlinear. This distinction matters because circuits made only of linear elements are easier to analyze than circuits that include nonlinear parts. A linear element follows both superposition and homogeneity. If the input is current, then one current level produces one voltage response, and another current level produces another response in a predictable way.

An element is nonlinear if it does not satisfy superposition or homogeneity. Thermistors are examples of nonlinear circuit elements. These categories help describe how circuit parts behave and how a circuit responds to electrical signals.

Circuit Elements: Passive, Active, and Linear

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electric circuit elements

Circuit elements are the building blocks of an electric circuit. An electric circuit is the connection of these elements. In this context, circuit elements are often grouped by how they behave and whether they supply energy. One major group is passive elements. These elements do not generate energy. Common passive elements include resistors, capacitors, and inductors. The other group is active elements, which can generate energy. Generators, batteries, and operational amplifiers are typical...

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key terms and concepts

Learn how circuit elements are grouped as passive or active, and how linear and nonlinear behavior affects circuit analysis. Includes examples like batteries and thermistors.

Circuit Elements: Passive, Active, and Linear | 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.

electrical engineering

Circuit Elements: Passive, Active, and Linear

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