Equation of plane question?

Microwave Question, Linearly Polarized Waves?

• that's my homework of Microwaves class. it's about plane waves in lossless medium. -> Suppose that a plane wave, which is linearly polarized at x-direction, is propagating in +z direction in free space with a frequency of f=300MHz. Write down the instantaneous (time domain) expressions of electric and magnetic field. i know that the wave can be written as ~E=Eo*[e^(-jkz)]*(~ex) Eo is constant amplitude j is the sqrt[-1] k is the wave number ~ex is the unit vector of x. so, i know the equation but not sure its only electric field or magnetic or both. i also know that magnetic field is orthogonal to electric field. But to be sure i am asking this long question. Thank You!

• Answer:

  The expression for magnetic field will have exactly the same form as that for the electric field, they will be in phase, and both sinusoids (comlex exponentials), so the form will be the same for electric and magnetic fields, essentially jsut replace E's with B's or H's or whatever you prefer to use ;) The actual 'direction' of the E and B fields wil be different of course (Orthogonal), but thats just a matter of using a different unit vector and the good old right hand rule. have a look at wikipedia http://en.wikipedia.org/wiki/Linear_polarization