1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Low pass filter circuit questions

  1. Feb 25, 2012 #1
    1. The problem statement, all variables and given/known data

    Why does a low pass active filter give a constant gain and no filtering when the capacitor is removed? What type of circuit does this become? Support your answer with equations.


    Does the amplitude eventually roll off as the frequency was increased toward to a very large value? how would you determine this value? Why does this occur?

    2. Relevant equations

    not sure

    3. The attempt at a solution

    i dont know where to start really. Our professor is a week behind in his lectures and he assigned this.. I am stuck on these two questoins.
  2. jcsd
  3. Feb 26, 2012 #2


    User Avatar

    Staff: Mentor

    Search for a low pass filter constructed around an OP-AMP.
  4. Feb 26, 2012 #3
    The capacitor is the frequency dependent component and, as nascent oxygen has indicated, an op amp has some frequency dependency
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook