Identify the circuit

Concept:

Capacitor shows different characteristics when the frequency is varied.

The capacitive reactance is defined as:

\(X_C = \frac{1}{2\pi fC}\)

When f = 0

X_C  = ∞. This implies that the capacitor will be like an “Open circuit”.

When f = ∞

X_C = 0. This implies that the capacitor will be like a “Closed-circuit”.

Calculation:

The given circuit can be redrawn at the f = 0 by making the capacitors open the circuit:

Applying voltage divider potential at the positive terminal will be V_in(R₄)/(R₂+R₄), which will appear across the battery's negative terminal using virtual ground concept.

From there we may conclude that output is not zero at f=0

The given circuit can be redrawn at the f = ∞, by making the capacitors open circuit.

The feedback element is shorted and the circuit is redrawn as:

The output will be of some finite value due to the negative feedback.

The resultant filter is the Band Stop Filter