Electromagnetics Specifically depth problems.

1. Dec 1, 2008

apalmer3

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

A plane wave of 1 MHz frequency in free space is incident normally on a copper
surface [$$\sigma$$=5.8*10^7, $$\mu$$r=1, and $$\epsilon$$r=1]. If the magnetic field strength at the surface is 1 mA m-1, find the depth at
which it is 2.5% of this value. Calculate the value of electric field on the surface
of the copper. Make a comment on the total power propagated inside the copper.

3. The attempt at a solution

I am mostly concerned with how to find the depth at which the magnetic field is 2.5% of its original value. I simply don't have any resources on how to calculate this. Could anybody point me towards the correct equations? Thanks!