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: When placed in series a coil and capacitor resonate at a frequency of 2251Hz and when

  1. Apr 9, 2010 #1
    When placed in series a coil and capacitor resonate at a frequency of 2251Hz and when placed in parallel they resonate at a frequency of 2228Hz. At parallel resonance it is also found that a current of 5mA flows from the supply when the supply voltage is 25V r.m.s.
    Determine the value of the capacitor and the inductance and the resistance of the coil.




    fs = 1/(2Π√LC)

    fp = 1/2Π √(1/LC-R^2/L^2 )



    From the information given, I can work out the parallel resistance:

    R = vs / I
    = 25 / 0.005
    = 5000 Ohms.

    But from this I don't know which way to go. Any guidance would be much appreciated.
     
  2. jcsd
  3. Apr 9, 2010 #2

    berkeman

    User Avatar

    Staff: Mentor

    Re: When placed in series a coil and capacitor resonate at a frequency of 2251Hz and



    The wikipedia.org article on RLC resonance is pretty good, and should help you out.

    http://en.wikipedia.org/wiki/RLC_series_circuit

    .
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook