Parallel Circuit Definition Resistors are said to be connected in parallel when the same voltage appears across every component. With different resistance values, different currents flow through each resistor. The total current taken from the supply is the sum of all the individual resistor currents. The equivalent resistance of a …

Read More »## Series Circuit Definition | Series Circuit Examples

Series Circuit Definition Resistors are said to be in series when they are connected in such a way that there is only one path through which current can flow. This means that the current in a series circuit is the same in all parts of the circuit. Series Circuit Characteristics …

Read More »## Linearity in Circuits

Consider the relationship between voltage and current for a resistor (Ohm’s Law). Suppose that c current I1 (the excitation or input) is applied to a resistor, R. then the resulting voltage V1 (the response or output) is \[{{V}_{1}}={{I}_{1}}R\] Similarly, if I2 is applied to R, then V2=I2R results. But if …

Read More »## Electrical Symbols | Electrical Drawing Symbols

A symbol is a simple graphical representation of some type of component, device, and load that can be drawn easily on a two-dimensional scale. On electrical or electronic diagrams, symbols are used to represent electrical components. Electrical symbols used in industry today are what engineers use to identify parts of …

Read More »## Sinusoidal Waveform or Sine Wave in Electricity

Because of the importance of sinusoidal functions, I will devote this section to a review of some of their properties. Let us being with the sine wave, $\begin{matrix} v(t)={{V}_{m}}\sin (\omega t) & \cdots & (1) \\\end{matrix}$ Which is sketched in figure (1). The amplitude of the sinusoid is Vm, which …

Read More »## Electric Current | Unit of Electric Current

The primary purpose of an electric current is to move or transfer charges along specified paths. This motion of charges constitutes an electric current, denoted by the letters i or I, taken from the French word “intensite”. Formally, The basic unit of current is the ampere (A), named after …

Read More »## Phasors in Electric Circuits

The phasor method of analyzing circuits is credited generally to Charles Steinmetz, a famous electrical engineer with the General Electric Company in the early part of this century. To begin, let us recall the general sinusoidal voltage, $\begin{matrix} v={{V}_{m}}\cos (\omega t+\theta ) & \cdots & (1) \\\end{matrix}$ If the frequency …

Read More »## Active Components and Passive Components in Electric Circuits

We may classify circuit element into two broad categories, passive elements, and active elements, by considering the energy delivered to or by them. A circuit element is said to be passive if the total energy delivered to it from the rest of the circuit is always non-negative. That is, for …

Read More »## RMS Value| RMS Voltage | RMS Current

Periodic currents and voltages deliver an average power to resistive loads. The amount of power that is delivered depends on the characteristics of the particular waveform. A method of comparing the power delivered by different waveforms is therefore very useful. One such method is the use of RMS or effective …

Read More »## RLC Series Circuit Analysis

The series RLC circuit, shown in figure 1, is the dual of the parallel circuit. Therefore all the results for the parallel circuit have dual counterparts for the series circuit, which may be written down by inspection. In this section, we shall simply list these results using duality. The initial …

Read More »## Average Power Formula | Instantaneous Power Formula

In linear networks which have inputs that are periodic functions of time, the steady-state currents and voltages produced are periodic, each having identical periods. Consider an instantaneous power $\begin{matrix} p=vi & \cdots & (1) \\\end{matrix}$ Where v and i are periodic of period T. that is, $\begin{align} & v(t+T)=v(t) \\ & …

Read More »## Parallel RLC Circuit Analysis

One of the most important second order circuits is the parallel RLC circuit of figure 1 (a). Fig.1 (a): Parallel RLC Circuit We shall assume that at t=0 there is an initial inductor current, $\begin{matrix} i(0)={{I}_{o}} & \cdots & (1) \\\end{matrix}$ And an initial capacitor voltage, $\begin{matrix} v(0)={{V}_{o}} & \cdots …

Read More »## Inductor Types and Symbols

In spite of the great number of different kinds of inductors, only a few schematic symbols are needed to represent them. Filter Choke A filter choke for a power supply is shown in figure 1 (a), and its symbol is shown in figure 1(b). Fig.1: Iron Core Choke Coil: (a) …

Read More »## RL Circuit Time Constant | Universal Time Constant Curve

When a series RL circuit is connected across a supply, voltage and current transients occur until the current attains a steady-state condition. Consider the circuit of figure 1, where R represents the coil’s resistance or an external resistance. When the switched is closed, current begins to flow into the inductance. …

Read More »## RC Circuit Time Constant | Charging Discharging of Capacitor

When a discharged capacitor is suddenly connected across a DC supply, such as Es in figure 1 (a), a current immediately begins to flow. At time t1 (Figure 1 (b)), the moment the circuit is closed, the capacitor acts like a short circuit. The in-rush current iC is at its …

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