parallel inductance capacitance

Discussion in 'Homework Help' started by regexp, Nov 20, 2010.

1. regexp Thread Starter New Member

Nov 20, 2010
24
1
Hi,

I need to find the resulting vector of a resistor in parallel with a capacitance in parallel with an inductance.

The complex impedances are -J50 and J200. The value of the resistor is 100Ω

So i have $\frac{1}{\frac{1}{100}+\frac{1}{-j50}+\frac{1}{j200}}$

In the key to my textbook this should equate to 55.47$\angle$ -56.31.

And i don't get that...

if I add the two complex impedances i have 100 + J150.

$\frac{1}{1/100 +1/150} = 60 \angle 56.31$

2. t_n_k AAC Fanatic!

Mar 6, 2009
5,448
790
The text answer is correct - you need to re-check your method.

The components are in parallel - not in series. Adding the two complex terms as you have done would be OK if they in series.