Engineering Board Exam Reviewer · Passive Filters · hard

A first-order RC high-pass filter delivers 3.5 V rms for a 10 V rms input at 500 Hz. What is its cutoff frequency?

  1. 1.43 kHz
  2. 0.175 kHz
  3. 0.5 kHz
  4. 1.34 kHz

Answer

D. 1.34 kHz

Solution

VoutVin= xsqrt(1+x2)=0.35 with x=f/fc. Squaring: x2/1+x2=0.1225 x2=0.1396 x=0.3736. fc=f/x=500/0.3736=1.34 kHz.

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