This questain is about Thevenin's equivalent circuit?

Question

Why its necessary to remove the source and complete the circuit by a link insteed of shorting the terminals of supply?

Answer 1

In a simulation you may short out the voltage source(s), but in real life if you were to short out a real voltage source it would get very hot and probably burn up.

Even so, there are some simulation softwares that will see an infinite current flowing in the shorted-out voltage source and give an error. To eliminate the computational error of infinite current times zero resistance, remove the source and replace it with a short.

For real circuits you need to remove the voltage source(s) and replace them with zero-ohm shorts.

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