- #1

unscientific

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## Homework Statement

Part (a): Show wave equation for E can be reduced to that.

Part (b): Show impendance of material is:

Part (c): Find skin depth.

## Homework Equations

## The Attempt at a Solution

I've got parts (a) and (b) solved, part (c) I've worked it out, but I'm not sure how to use the information of senstivity of ##1 \mu V m^{-1} ##.

The characteristic timescale during transient state where charges flow in a conductor is ##\tau = \frac{\epsilon_0 \epsilon_r}{\sigma}##.

For a low frequency regime, ##\tau << \frac{1}{\omega}##.

Substituting, ##\frac{\epsilon_r \epsilon_0}{\sigma} << \frac{1}{\omega}## and finally ##f << \frac{\sigma}{2\pi \epsilon_r \epsilon_0} = 0.01 Hz##.

Now to find skin depth, d:

[tex]d = \sqrt{\frac{2}{\mu_0 \mu_r \sigma \omega}}[/tex]

Using ##E = \frac{\sigma}{\epsilon_0 \epsilon_r}##,

[tex]d = \sqrt{\frac{2}{\mu_0 \mu_r \epsilon_0 \epsilon_r E \omega}} = 2.67 x 10^4 m[/tex]

What's the point of giving the sensitivity of the receiver?