# Resonance Curve - Do I have enough info?

1. Mar 27, 2009

### phyzmatix

1. The problem statement, all variables and given/known data

For a sinusoidally driven RLC circuit.

Draw accurate resonance curves for C = 0.01uF, L = 0.01mH and
i) R = 20 ohm
ii) R = 200 ohm

2. The attempt at a solution

Believe it or not, I do not have a single example of resonance curves in any of my textbooks. However, from my internet searches, I believe the resonance curves are supposed to look something like the one here:

http://hyperphysics.phy-astr.gsu.edu/HBASE/electric/imgele/qresi.gif" [Broken]

I know that at resonance,

$$i_0=\frac{V_0}{R}$$

also

$$\omega_0 = \frac{1}{\sqrt{LC}}$$

and that

$$i=i_0\cos(\omega t + \phi)$$

But how do I bring this all together into something coherent? Am I not supposed to know what V0 is?

Thanks!
phyz

Last edited by a moderator: May 4, 2017
2. Apr 1, 2009

### Redbelly98

Staff Emeritus
If you're not given Vo, you could plot the ratio Irms/Vorms instead of just Irms.

This will involve calculating the complex impedance Z for the circuit, which can be used to get Irms/Vorms.