The input frequency of a single-pole, low-pass active filter increases from 1.5 kHz to 150 kHz. If the critical frequency is 1.5 kHz, the gain decreases by ________.
A)60 dB
B)3 dB
C)40 dB
D)20 dB

Question

Quizplus · Accepted Answer

The gain of a single-pole low-pass filter decreases by 20 dB per decade. From 1.5 kHz to 150 kHz is two decades (1.5 kHz to 15 kHz and 15 kHz to 150 kHz), so the gain decreases by 40 dB.

The Input Frequency of a Single-Pole, Low-Pass Active Filter Increases