In a positive feedback system, the positive feedback signal & amplifier input signal are what?

Question

is it 90 deg. out of phase

180 deg out of phase

45 deg out of phase

or is it in phase?

Answer 1

Could be in phase or could be 180 degrees out, depending on the circuit connections. Or it could be any of the others at various frequencies.

But I think he is looking for "in phase".

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