Question

In an inverting amplifier the two input terminals of an ideal op amp are at same potential because

Answer 1

In an inverting amplifier the two input terminals of an ideal op amp are at same potential because the CMMR ( common mode rejection ratio) of an ideal op-amp is infinite which means there will be zero output when no input is applied. Since the output of the op-amp is the difference between potentials of the two inputs multiplied by some constant called gain, for inputs at same potential the output will be zero.

Hence, to ensure that no unwanted voltage (noise) is being amplified and reflected at the output terminal, the difference between the potentials of the two inputs is kept zero.