Basic Concepts related to AC circuit.

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Basic concepts related to AC circuit :-Reactance :-

     Reactance is defined as the opposition produced in ac circuit by reactive element auch as capacitor or inductor.
It is mejores by 'X' and its unit is 'ohm'.

The reactance is devided into two parts:-
  • Inductive reactance (XL).
  • Capacitive reactance (XC). 
  1. Inductive reactance (XL):-
         Inductive reactance is defined as opposition produced in ac circuit by inductor.
                     XL = 2ฯ€FL
Its unit is ohm
2. Capacitive reactance (XC) :-
         Capacitive reactance is defined as opposition produced in ac circuit by capacitor.
                    XC  = 1/2ฯ€FC
It's unit is also 'ohm'.

Impedance :- 
    Impedance is defined as opposition produced by combination of resistance and reactance in ac circuit.
It's unit is 'ohm'
                    Z  = √ R^2 + X^2


Types of power :-
  1. Real or true or active power (P).
  2. Reactive or imaginary power (Q).
  3. Appearent power (S).
1. Active power (P):-
    It is defined as product of voltage, current and cos of angle between voltage and current.
                    P = V×I×cosฮฆ
It's unit is watt or kW.

2. Reactive power (Q):-
     It is defined as the product of voltage, current, and sin of angle between voltage and current.
                    Q = V×I×sinฮฆ
It's unit VAR or kVAR.(volt ampere reactive )

3. Apparent power(S) :-
     It is defined as the product of voltage and current.
                    S = V×I
It's unit is VA or KVA.

Power factor:- 
    It is defined as cosine angle between voltage and current.
    Power factor = real power /apparent power
                 Power factor = cosฮฆ

Admittance (Y):-
      Admittance is defined as the reciprocal of impedance or it is combination of conductance and susceptance.
                    Y = 1/Z
Its unit is mho or Siemens 

Conductance(G):-
      It is defined as the ratio of resistance to square of impedance.
                   G = R/Z^2
Its unit is mho or Siemens.

Susceptance(B):-
     The susceptance is defined as define as ratio of reactance to square of impedance.
                  B = X/Z^2


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