# complex numbers homework

Discussion in 'Homework Help' started by davy1tfc, May 21, 2011.

1. ### davy1tfc Thread Starter New Member

May 21, 2011
2
0
Hi all i was wondering if you could help me out with this question

10v 47.7khz 0 deg supply

10nF capacitor in parallel with a 1mH coil and a 100 ohm resistor.

1. determine the capacitive reactance in complex form.
2. determine the inductive reactance in complex form.
3. determine the circuit dynamic impedance.
4. determine if the circuit is in a state of resonance.

I am having problems with 3 and 4 and any help would be much appreciated.

thanks

davy

2. ### davy1tfc Thread Starter New Member

May 21, 2011
2
0
i am not sure if the question is wrong as i see alot about dynamic resistance and and total circuit impedance but have not seen alot about circuit dynamic impedance. a simple formulae would be a great help please.

3. ### jegues Well-Known Member

Sep 13, 2010
735
44
A quick google yields this definition for dynamic impedance,

"The impedance of a circuit having an inductance and a capacitance in parallel at the frequency at which this impedance has a maximum value. Also known as rejector impedance."

Also, what are typical charactersitics of a circuit that is in resonance?