Engineering Board Exam Reviewer · Passive Filters · easy
At the cutoff frequency of a first-order filter, the output voltage is what fraction of the maximum (passband) output?
- 0.5
- 0.637
- 0.707
- 0.9
Answer
C. 0.707
Solution
The cutoff (or -3 dB) frequency is where the gain has fallen to 1/ 2=0.707 of its passband value.
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