# RLC Circuit

Discussion in 'Homework Help' started by k31453, May 22, 2013.

Not open for further replies.
1. ### k31453 Thread Starter Member

May 7, 2013
54
0

This is my question 1.

and this is my question 2.

in a RLC series circuit show above are replaced following : R=500Ω L=0.4mH and C=100pF
the circuit is connected to the terminals of an ac source with an rms voltage of 1V, and a variable frequency calculate the following
A) resonant frequency
ans: f = 1/2*pi*sqrt(LC)
= 1/(2*pi*sqrt(0.0004 * 100 * 10^-12)
= 795.77 Khz

b) the inductive and capacitive reactance at resonance
ans: XL = 2*pi*f*L
= 2*pi* 795.775*10^3*0.0004
= 2000 ohm

Xc = 1/(2*pi*f*C)
= 1/(2*pi* 795.775*10^3 * 100 * 10^-12)
= 1999.9998 ohm

C) the impedance at resonance

ans : impedence of resonance is resistance of circuit : z = R = 500 ohm

D) the rms current at resonance
ans: I = V/R = 1/500 = 0.002A

E) the rms voltage across each element at resonance
Ans: Vr = IR
= 0.002 * 500
= 1V

VL = IXL
= 0.002 * 2000
= 4V

Vc = IXc
= 0.002 * 1999.99
= 3.99998 V

So am i doing it right?? because
i got another reply that says this :

2. ### WBahn Moderator

Mar 31, 2012
23,160
6,974
If you want to go back and track your units, I will look through this. Otherwise it's not worth my time.

3. ### k31453 Thread Starter Member

May 7, 2013
54
0

yeah i know there is mistake he did he use 0.4H instead of 0.4mH

Nov 25, 2009
5,175
1,284