Resistance, Inductance and capacitance

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Resistance:

Resistance is the opposition offered by the conductor to flow of current.

The symbol of Resistance is 

Mathematically, V= IR

                 or, R = V/I

The ratio of voltage to the current is known as Resistance.

The Resistance of transmission line is uniformly distributed along its whole length.

Effective Resistance = (Power loss in conductor) / I^2

We know that,

             R =   ρ * l / a

                  Where,    ρ = Resistivity

                                   l  = Length

                                   a  = Cross-section area

Now, we can define;

Resistance is directly proportional to length and inversely proportional to the area of conductor.


Inductance:

When an alternating current flows through a conductor, a changing flux is setup which links conductor due to this flux linkage, the conductor produces inductance.

The symbol of inductance:

Mathematically, Inductance is defined as flux linkage per Ampere.

          L = ψ /I       (Henry)

   or, L = NΦ / I     (Henry)

       Where, Φ = magnetic flux 

                     Ψ = flux linkage

Inductance can be defined as the opposition of direction and magnitude of change of current.

              V = L * dI/ dt     (volt)


And also, Inductor stores energy in the form of magnetic field.

E[L] = 1 /2 L* I ^ 2   (joules

Capacitance:

When any two conductors are separated by an insulating material, it will for capacitance between two conductors which is defined as charge per unit potential difference.

           C = Q / V  (farad)

        Where, Q = charge

                     V = potential difference

The symbol of capacitance: 

And also, capacitor stores energy in the form of electric field.

         E[C] = 1 / 2 C * V ^ 2     (joules)






        

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