Question

In the circuit given below, the Roll-off of the filter is _______________

(a) 20 dB/decade

(b) 40 dB/decade

(c) 60 dB/decade

(d) 80 dB/decade

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This question is from Ideal LPF, HPF, BPF and BSF Characteristics in division Signal Transmission Through Linear Systems of Signals and Systems

Answer 1

The correct choice is (a) 20 dB/decade

To explain: The given filter is a first order Band Pass Filter. Also, the Roll-off of the filter depends upon the order of the filter. For a first order it is 20dB/decade, for second order it is 40dB/decade, and so on.

Therefore, the Roll-off of the filter = 20 dB/decade.