Question

what is the difference between thevenin's and Norton theorem

Answer 1

Norton’s theorem is converse of Thevenin’s theorem in the respect that Norton equivalent circuit uses a current generator instead of voltage generator and the resistance RN (which is the same as RTh ) in parallel with the generator instead of being in series with it. 

Thevenin’s theorem is a voltage form of an equivalent circuit where as Norton’s theorem is a current form of an equivalent circuit.