Magnetic field from electric field given a function of time

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The discussion focuses on deriving the magnetic field vector from a given electric field vector of an electromagnetic wave in free space. The electric field is expressed as E = f(t-z/c0)x, where f(t) involves an exponential function. Participants discuss the application of Maxwell's equations, particularly Faraday's law, to relate the electric and magnetic fields. The complexity of the calculations is highlighted, especially when taking the curl of the electric field and integrating. The physical nature of the wave, including its polarization and propagation direction, is also considered essential for a complete analysis.
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Homework Statement


An em wave in free space has an electric field vector E = f(t-z/c0)x where x is a unit vector in the x direction and f(t)= exp(-t22)exp(j2πv0t). Describe the physical nature of this wave and determine an expression of the magnetic field vector.

Homework Equations


Maxwells faradays law ∇XE=-μ δH/δt

3. The Attempt at a Solution [/B]
I have two things I´m not so sure about. Given f(t) will the electric field now become
E= exp(-(t-z/c0)22)exp(j2πv0(t-z/c0))x

If so, when I use the curl of the field (dEz/dy-dEy/dz)x+(dEx/dz-dEz/dx)y+(dEy/dx-dEx/dy)z
I assume everything is 0 except for dEx/dz which I´m not sure because it´s multiplied by a unit vector y.
when I derivate by z I then have to intergrate by on both sides of the max eq. but I get a very complex integral.
So where I did I get lost.
Thanks in advance.
P.S. Describing the physical nature of this wave? Do I need to state that the wave is linaear homogenous and Isotropic.
 
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Hi. For the physical nature of the wave, you can ask yourself: is it polarized, and if yes in which direction? is it propagating, and if it is in which direction? how is the amplitude: constant or changing?
For the B field, you can start by determining the charges and currents present. Then you should be able to use Maxwell's equations to determine a simpler relation between E and B...
 
Scratch the second part of my answer, you can actually use ∇ × E = –μ ∂B/∂t directly, as you started:
the curl is easy to take, then integrating with respect to time becomes easy as well since t and z/c0 enter in the equation in (anti-)symmetric way...
 

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