Page 101 - Basic Electrical Engineering

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I Rt where I is the current flowing, R is the resistance value, and t is the time.

Energy stored in a capacitor is where C is the capacitance of the

capacitor and V is the potential across it. For an inductor, the energy stored is
2
1/2 L I where L is the inductance and I is the current flowing through it.
The formulas used to calculate the value of R, L, and C are:

[ρ is the resistivity, ℓ is the length and a is the area of cross section of

the wire]

[μ is the permeability, N is the number of turns, A is the area of the

coil ℓ the length of the flux path]

[ε is the permittivity of the material between the two plates, A is the

area of each plate, and d is the distance between the plates.
Analysis of networks or circuits involve calculation with respect to finding

out current flowing through an element, voltage across a component, power
dissipated or stored in a circuit component, etc.
Laws and theorems have been introduced to make the task of network

analysis simpler. To solve a particular network problem, a number of
alternative methods or theorems can be applied. Experience will guide us as

to which one will be the quickest or easiest method to apply. In this chapter
the circuit laws and theorems, voltage sources, various methods of

connection of circuit components and their transformations, etc. will be
discussed. Only dc networks will be taken up in this chapter.

2.2 DC NETWORK TERMINOLOGIES, VOLTAGE, AND CURRENT SOURCES

Before discussing various laws and theorems, certain terminologies related to
dc networks are described first.