Week of 9/4

Try the following notebook

Download manipulating complex numbers in Mathematica.

Also, take a look at Mathematica Tips and Tricks.

A real amplitude and phase measurement. Top figure shows the amplitude of the transmitted and reflected electric fields. Bottom are the corresponding amplitudes.

when is it ok to assume physical expressions are comples?

Consider the forced, damped, simple harmonic oscillator.

$\ddot{x} + \gamma \dot{x} + \omega_0 ^2 = F/m$