Electrical Concepts

Reactance is defined an electrical quantity due to which alternating current is opposed by inductor or capacitor or combination of both of them in a circuit. Impedance is the net opposing factor to alternating current. Reactance may also be called impedance offered either by inductor or capacitor. Reactance is denoted by X and impedance by … Read more

What is j Operator? j Operator is a mathematical operator which when multiplied with any vector, rotates that vector by 90 degree in anti-clock wise direction. Just like symbols x, +, – etc. are used with numbers for indicating certain operations to be performed on those numbers, j operator is used to indicate the counter-clock … Read more

The main difference between Resistance and Impedance is that resistance opposes the flow of DC & AC current whereas Impedance only opposes the flow of AC current. Impedance is having meaning only in AC circuit. It does not have any meaning in DC circuit. Another major difference between resistance and impedance is that impedance may … Read more

Statement of Maximum Power Transfer Theorem in AC Circuit: In AC circuit, the maximum power transfer theorem is stated as: In a linear network having energy sources and impedances, the maximum amount of power is transferred from source to load impedance if the load impedance is the complex conjugate of the total impedance of the … Read more

What is Voltage Division Rule? Voltage Division Rule states that the total voltage applied across a series connection of multiple resistors is divided among the resistors in proportional to their resistance.  This means, the voltage drop will be maximum across the resistor having maximum value of resistance. Likewise, it will be minimum for resistor having … Read more

What is Current Division Rule? Current Division Rule states that the total current divided into either of the parallel combination of two resistance or impedance is inversely proportional to the value of resistance / impedance. It basically tells us how the current is divided in the parallel connected resistance. This rule is applicable for AC … Read more

Norton’s Theorem states that any linear bilateral circuit consisting of independent and or dependent sources viz. voltage and or current sources can be replaced by an equivalent circuit consisting of a current source in parallel with a resistance. The current source is the short circuit current across the load terminals and the resistance is the … Read more

Statement of Substitution Theorem: Substitution Theorem states that any branch of a DC bilateral circuit can be substituted by a combination of various circuit elements, provided the current & voltage across the branch remains unchanged. Basically, this theorem tells us the boundary condition to replace a circuit branch. If the value of current and voltage … Read more

Reciprocity Theorem states that, the value of current due to a single source in any particular branch of circuit is equal to the value of current in the original branch where the source was placed when the source is shifted to that particular branch of circuit. This theorem is only applicable for a reciprocal network … Read more

Superposition theorem states that the resultant current in any branch in a liner network having a number of sources, is the algebraic sum of the current that would be produced in it, when each source acts alone replacing all other independent sources by their internal resistance. This theorem is very useful for solving a network … Read more