Explain the significance of virtual ground in an operational amplifier?

Ans: Significance of Virtual Ground: Fig. (a) illustrates the circuit diagram of basic Inverting Amplifier. In this figure, the non-inverting terminal  is  grounded and input signal is applied to inverting terminal via resistor R₁. However, difference input voltage is ideally zero: that is, voltage at the inverting terminal (v₂) is approximately equal to that at non-inverting terminal (v₁). Or we can say,  inverting  terminal  voltage  v₂  is  approximately  at  ground  potential. Hence, inverting terminal is said to be at Virtual Ground. This notion is extremely useful in analysis of closed loop Op-amp circuits.