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Parallel Circuit Definition | Parallel Circuit Examples

Circuit Diagram for Parallel Connected Resistors

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 …

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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 …

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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 …

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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 …

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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 …

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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 …

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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 …

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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 …

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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) \\ & …

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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  …

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Inductor Types and Symbols

Typical power supply inductor

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) …

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