Engineering Board Exam Reviewer · Passive Filters · easy
Beyond the cutoff frequency, the output of a first-order passive filter rolls off at
- 40 dB per decade
- 3 dB per decade
- 10 dB per decade
- 20 dB per decade
Answer
D. 20 dB per decade
Solution
A single RC or RL section produces a roll-off of 20 dB per decade (about 6 dB per octave).
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