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

Gli elementi del circuito sono gli elementi costitutivi di base di un circuito elettrico. Possono essere classificati come elementi attivi e passivi.
Gli elementi attivi possono generare energia, mentre gli elementi passivi assorbono energia.
Esempi di elementi attivi includono sorgenti di tensione o corrente, mentre resistori, condensatori e induttori sono esempi di elementi passivi.
Gli elementi del circuito possono essere ulteriormente classificati come lineari o non lineari.
Un circuito o un elemento è considerato lineare se l'eccitazione e la risposta dell'elemento seguono i principi di sovrapposizione e omogeneità.
Supponiamo che una tensione v1 porti a una risposta i1 e una tensione v2 porti a una risposta i2. Se l'elemento risponde alla somma delle tensioni con la somma delle risposte, allora soddisfa il principio di sovrapposizione.
Inoltre, la proprietà di omogeneità è soddisfatta quando moltiplicando l'input di un dispositivo lineare per qualsiasi costante si ottiene una moltiplicazione equivalente dell'output.
Gli elementi lineari come resistori, condensatori e induttori presentano caratteristiche lineari.
Elementi come i termistori non sono lineari, in quanto non rispettano questi principi.

elementi del circuito elettrico

Gli elementi circuitali sono gli elementi costitutivi di base di un circuito elettrico. Sostanzialmente, un circuito elettrico è l'interconnessione di questi. All'interno dei circuiti elettrici si possono trovare due tipi di elementi: passivi e attivi. Gli elementi attivi hanno la capacità di generare energia, mentre gli elementi passivi no. Gli elementi passivi includono componenti come resistori, condensatori e induttori, mentre gli elementi attivi comprendono tipicamente generatori, batterie e amplificatori operazionali.

Gli elementi attivi più cruciali sono le sorgenti di tensione o corrente, che generalmente forniscono energia al circuito collegato. Esistono numerosi modi per classificare gli elementi del circuito. Ad esempio, distinguere i modelli lineari da quelli non lineari è fondamentale perché i circuiti composti interamente da elementi circuitali lineari sono più semplici da analizzare rispetto a quelli con alcuni elementi non lineari.

Un elemento o circuito, è considerato lineare se l'eccitazione e la risposta dell'elemento soddisfano determinate condizioni. Un elemento lineare soddisfa sia le proprietà di sovrapposizione che quelle di omogeneità. Considera uno scenario in cui l'eccitazione è la corrente (i) e la risposta è la tensione (v). Se l'elemento è sottoposto ad una corrente (i1), questo fornisce una risposta (v1). Allo stesso modo, quando l'elemento è esposto a un'altra corrente (i2), suscita una risposta (v2).

Qualsiasi elemento del circuito, che non soddisfi né il principio di sovrapposizione né quello di omogeneità è classificato come non lineare. I termistori sono esempi di tali elementi non lineari.

Elementi del Circuito Elettrico

Gli elementi del circuito sono gli elementi costitutivi di base di un circuito elettrico. Possono essere classificati come elementi attivi e passivi.
Gli elementi attivi possono ...

Education

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JoVE Core

Electrical Engineering

Ingegneria elettrica

Unit 1

Unità 1

Basics of Electric Circuits

Fondamenti dei circuiti elettrici

KEY TERMS AND CONCEPTS

TERMINI E CONCETTI CHIAVE

Electric Circuit Elements

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

circuit-elements-passive-active-and-linear

charge and current

Electric Charge in Circuits

Electric charge in circuits explains how charged particles behave in matter and how current is produced. Everyday static effects, like a wool sweater sticking to the body or a shock from a carpet, show charge in action. Charge is an inherent property of atomic particles and is measured in coulombs (C). Matter is made of atoms with electrons, protons, and neutrons. Electrons carry a negative charge (-e), and protons carry a positive charge (+e). These two charges have the same magnitude. An...

voltage

Voltage in Electric Circuits

Voltage in electric circuits is the energy needed to move electric charge between two points. It is also called electromotive force, or EMF. In most circuits, an external force such as a battery provides this energy for electron movement in a conductor. The voltage between points a and b is written as v_ab. It is defined as the work, or energy, needed to move a unit charge from point a to point b. In the equation, w is the energy in joules and q is the charge in coulombs. Voltage is measured...

power and energy

Circuit Power, Absorption, and Supply

Circuit power, absorption, and supply explain how much energy an element uses or delivers in an electric circuit. These ideas matter in electrical engineering because power and energy calculations help describe circuit behavior. A 100-watt light bulb, for example, emits more light than a 60-watt bulb, so wattage is a useful measure in real devices. Power is the time rate of expending or absorbing energy. It is measured in watts, written as W. The relation between power and energy uses the...

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...

circuit terminology

Circuit Parts: Branches, Nodes, and Loops

Circuit parts like branches, nodes, loops, and meshes help describe how electrical networks work. An electrical network is a system of connected elements, such as resistors, capacitors, inductors, and voltage or current sources. Unlike a circuit, a network does not have to form a closed path. A circuit is also made of connected electrical elements, but it must include one or more closed paths. These loops let current flow continuously, which is what makes the circuit operate. Because of this,...

independent and dependent sources

Circuit Source Symbols and Controls

Circuit sources in electrical circuits can be independent or dependent. They provide the power a circuit needs to operate. Independent voltage sources supply a fixed voltage, and independent current sources supply a fixed current. Their output does not change because of other parts in the circuit. These sources use standard symbols in circuit diagrams. An independent voltage source is shown with + and - signs to mark the potential difference. An independent current source is shown with an...

ohm's law

Resistance and Conductance in Circuits

Resistance and conductance help explain how electric current moves through a circuit. Resistors are basic circuit parts made from metallic alloys or carbon compounds. They are used to model how a material resists current and to control and regulate electrical power in a circuit. Ohm's law describes the link between voltage and current across a resistor. The voltage across a resistor is directly proportional to the current through it. The constant that sets this relationship is resistance.

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

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,...

voltage dividers

Series Resistors and Voltage Split

Series resistors split voltage across a circuit. In a series setup, resistors are linked one after another. The same current flows through each resistor in the chain. To analyze this behavior, Ohm's law is used to relate voltage, current, and resistance. Kirchhoff's voltage law says the voltages around a series loop add up to the source voltage. That means the current in the circuit equals the source voltage divided by the total resistance in series. The current value can then be used in Ohm's...

current dividers

Parallel Resistors and Current Division

Parallel resistors share the same two nodes, so each resistor has the same voltage across it. In this circuit setup, Kirchhoff's current law applies. The source current equals the sum of the currents through each branch. Ohm's law helps find the branch currents from the source voltage and the resistor values. The source current is equal to the source voltage times the sum of the reciprocals of the resistances. This makes it easier to calculate how current divides in the circuit. The current...

equivalent resistance

Delta-Wye Network Conversion

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design example: resistive touchscreen

Resistive Touchscreen Voltage Mapping

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 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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