Question

network theorem is valid for ac. if it is then why?

Answer 1

Network theorems are valid for all the circuit which contains lumped circuit elements. That is if a circuit contains an element which can be distinguished one by one then the network theorems can be applied. In simple words if a circuit contains elements which can be found individually i.e resistors, inductor, capacitors.

Hence in an Ac circuit we can clearly differentiate between elements use whether it is inductors or capacitors so network theorems can be applied just as we apply in dc networks. The only difference is that we should take care or Inductance and capacitance working. So conclusion is that network theorems can be applied to any type of circuit which contains lumped elements and is linearised i.e they operate around operating point.

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