Describe the concept of virtual ground with reference to op-Amp.

Describe the concept of virtual ground with reference to op-Amp.
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Answer :

In circuit point VA is virtual ground. Figure shows inverting amplifier using op-amp. In this circuit non-inverting terminal is connected to the actual ground. Due to this potential of inverting terminal become zero. Thus, inverting terminal is not actually connected to the ground. There after its potential is zero. Thus point VA is known as virtual ground point. This phenomenon of having zero potential without actually grounding is known as virtual ground concept.

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Answer :

Virtual ground concept:-In circuit point A is virtual ground. Figure shows inverting amplifier using op-amp. In this circuit non-inverting terminal is connected to the actual ground. Due to this potential of inverting terminal become zero. Thus, inverting terminal is not actually connected to the ground. There after its potential is zero. Thus point A is known as virtual ground point. This phenomenon of having zero potential without actually grounding is known as virtual ground concept.

Circuit diagram: 

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