Name: circuit linearity and resistor behavior
Uploaded: 2024-04-11T12:48:31.000Z
Duration: 1 min 17 s
Channel: JoVE

Considere una resistencia conectada a una fuente de voltaje variable. A medida que se aumenta el voltaje, se registra el valor de corriente correspondiente.
La representación gráfica revela una relación lineal entre el voltaje y la corriente.
Los circuitos en los que los parámetros del circuito permanecen constantes a pesar de los cambios en el voltaje o la corriente se denominan circuitos lineales.
Los circuitos lineales están compuestos por elementos lineales o fuentes lineales independientes, y satisfacen propiedades de homogeneidad y aditividad.
Este principio puede ayudar en el modelado de circuitos para predecir la corriente de la fuente cuando cambia la caída de voltaje a través de la carga.
Inicialmente, se determina la corriente a través de la resistencia de carga y la caída de voltaje a través de la resistencia superior.
A continuación, se obtiene la caída de voltaje a través de la rama central, que se utiliza para calcular la corriente a través de esa rama. La aplicación de KCL da la corriente total de la fuente.
Cuando cambia el voltaje de carga, la nueva corriente de la fuente se puede encontrar multiplicando una constante por la corriente anterior y sustituyendo los valores conocidos.
Sin embargo, el principio de linealidad no se aplica al cálculo de la potencia, ya que la potencia tiene una dependencia cuadrada de la corriente.

circuitos lineales

Un circuito lineal se caracteriza porque su salida tiene una proporcionalidad directa con su entrada, adhiriendo a la propiedad de linealidad, que engloba los principios de homogeneidad (escalamiento) y aditividad. La homogeneidad dicta que cuando la entrada, también conocida como excitación, se multiplica por un factor constante, la salida, conocida como respuesta, se escala correspondientemente por el mismo factor constante. Por ejemplo, si la corriente se multiplica por una constante 'k', el voltaje también experimenta un aumento de 'k' veces. La propiedad de aditividad estipula que la respuesta a una suma de entradas es igual a la suma de las respuestas a cada entrada individual aplicada por separado. En esencia, esta propiedad obliga a que el comportamiento del circuito permanezca consistente incluso cuando se combinan múltiples entradas. En particular, una resistencia se clasifica como un elemento lineal porque satisface las propiedades de homogeneidad y aditividad dentro de su relación voltaje-corriente. Generalmente, un circuito se considera lineal si y sólo si demuestra características tanto de aditividad como de homogeneidad. Tales circuitos lineales se componen exclusivamente de elementos lineales, fuentes lineales dependientes y fuentes independientes. Por el contrario, la expresión de potencia, que se define como la relación entre el cuadrado del voltaje y la resistencia, constituye una función cuadrática y, por lo tanto, cae dentro de la categoría de no linealidad en el contexto del análisis de circuitos.

Circuitos Lineales

Considere una resistencia conectada a una fuente de voltaje variable. A medida que se aumenta el voltaje, se registra el valor de corriente correspondiente.
El gráfico ...

Education

Educación

JoVE Core

Electrical Engineering

Ingeniería Eléctrica

Unit 1

Unidad 1

DC Circuit Analysis

Análisis de circuitos de CC

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

Linear Circuits

circuit linearity and resistor behavior

Circuit linearity describes how a circuit responds when its input changes. A linear circuit has an output that is directly proportional to its input. This behavior follows two rules: homogeneity and additivity.

Homogeneity means that if the input, or excitation, is multiplied by a constant factor, the response is multiplied by the same factor. For example, if the current is increased by a constant k, the voltage also increases by k times. Additivity means that the response to a sum of inputs equals the sum of the responses to each input applied separately.

A resistor is a linear element because its voltage-current relationship follows both homogeneity and additivity. A circuit is considered linear only when it has both properties. Linear circuits contain linear elements, linear dependent sources, and independent sources.

Power does not follow the same pattern. Its expression uses the square of voltage divided by resistance, so it is a quadratic function. That makes power a nonlinearity in circuit analysis.

Circuit Linearity and Resistor Behavior

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linear circuits

Circuit linearity describes how a circuit responds when its input changes. A linear circuit has an output that is directly proportional to its input. This behavior follows two rules: homogeneity and additivity. Homogeneity means that if the input, or excitation, is multiplied by a constant factor, the response is multiplied by the same factor. For example, if the current is increased by a constant k, the voltage also increases by k times. Additivity means that the response to a sum of inputs...

superposition theorem

Analyzing Circuits with Superposition

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norton's theorem

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key terms and concepts

Learn how circuit linearity depends on homogeneity and additivity, why resistors are linear elements, and why power is treated as nonlinear in circuit analysis.

Circuit Linearity and Resistor Behavior | 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 Linearity and Resistor Behavior

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