What is Virtual Ground ?
As the name indicates it is virtual, not real ground. For some purposes we can consider it as equivalent to ground. In opamps the term virtual ground means that the voltage at that particular node is almost equal to ground voltage (0V). It is not physically connected to ground. This concept is very useful in analysis of opamp circuits and it will make a lot of calculations very simple.
Virtual Ground - Opamp
Lets see how the virtual...