Chapter 1.5, Problem 87E

The opposition to current in an electrical circuit is called its impedance. The impedance $z$ in a parallel circuit with two pathways satisfies the equation

$\frac{1}{z}=\frac{1}{z_1}+\frac{1}{z_2}$

where $z_1$ is the impedance (in ohms) of pathway 1 and $z_2$ is the impedance (in ohms) of

pathway 2. (a) The impedance of each pathway in a parallel circuit is found by adding the impedances of all components in the pathway. Use the table to find $z_1$ and $z_2$

(b) Find the impedance $z$.