Network Theory Or Circuit Theory Overview


Network Theory is mainly Helps us to simplify any complex circuit.so,that we can easily calculate current, voltage through the electrical components that we are going to study.





Before going to study the Network Theory Or Circuit Theory let's understood the theory with basic understanding. Suppose you visit a Mall and you can see  there  many small shops (also can  say stand alone shops) ,from there we can conclude that this small shops are like Circuit and Mall is like Network.

Electrical components

In the study of network Theory Or Circuit Theory we have 3 fundamental electrical components ie. ..

    1. Resistor : Resistor is an electrical components that has an property to resist the flow                             of current .

         Symbol  : 

     2. Capacitor : Capacitor is an electrical components that has an property to Store the                                         charge .

         Symbol : 

     3. Inductor : An inductor is a passive electrical or electronic component that usually                                  use to Store the energy in the form of flux.

        Symbol : 

        

 In the study of network Theory Or Circuit Theory you have to know about the knowledge of linear graph also can the behaviour of linear graph,just like the graph of y=mx that's passing through origin.

The graph of y=mx (It's the graph that's passing through origin)

  


Note: A graph is said to be linear if it's characteristics is straight line passing through origin.befor draw the the graph you have  to consider four coordinate axis. You can say slope of the graph must be finite.

Let's study some basic graph that we are going use during our study of network Theory Or Circuit.

Graph : y= -2x 

                            


Graph : y = l x l 

      


It's an Non-linear graph, Touching origin is not linear but passing through origin is said to be linear.
                               f(0-h) = 0 Left hand limit 

                                f(0+h) = 0 Right hand limit 

                                f(0-h) = f(0) = f(0+h) Then the function is said to be continuous 

Graph : y = l x l now draw y ' = ?


This function is discontineous at origin . It's an Non-linear graph.This type of function is known as signum function 

Now let's talk about Ohm's law 

  In the year of 1826 the the George Simon Ohm's come up with a experimental law ie.

                                                v~i or i~v

Both the formulas are currect.The ohm is represented by Greak letter Omega.

Let's discuss v~i first eventually we all are familiar with this law v=iR , This law is similar the form of y = mx so we can say this law the characteristics of linear graph.

v = Ri  where  v = v(t) and i = i(t)  are both time dependent voltage or current.This the convention that all network Theory Or Circuit Theory books are use to represent the instantaneous voltage or current.

Now draw the graph of v~Ri



Where R the resistance of the circuit. From the slope of the graph we can calculate the resistance or verify the resistance of the circuit.

 Now the second form of Ohm's law i = Gv where G is known as Conductance represent by mho.

Now draw the graph of i = Gv 



This  is also a graph that is passing through origin,it's show  linear characteristics curve similar to y = mx.

Note : Both the law that we study above is the Ohm's law of network Theory Or Circuit Theory.

For example Dide is  an electrical components that show Non-linear  characteristics.