[an error occurred while processing this directive]

Propagation of a Plane Electromagnetic Wave

This Demonstration shows the oscillations of the strengths of the electric and magnetic fields in a part of a plane electromagnetic wave moving through empty space at a fixed time. As you move the slider to the right, the blue and red sinusoidal curves trace out the variations in the electric (blue) and magnetic (red) field strengths as a function of The electric and magnetic fields are in phase, in that the strength of the magnetic field is at maximum when the strength of the electric field is at maximum. The wave is polarized in the direction. The direction of propagation of the wave is perpendicular to the directions in which the field strengths vary.


  • [Snapshot]
  • [Snapshot]
  • [Snapshot]


The variable labeled strength is the electric field strength , in units of V/m. The corresponding magnetic field strength is in units of , where is the speed of light, equal to m/s. The variable labeled frequency could be taken to be a multiple of, for example, a common FM radio wave frequency of Hz, which has a wavelength of 3 m.
[an error occurred while processing this directive]

Mathematica »
The #1 tool for creating Demonstrations
and anything technical.
Wolfram|Alpha »
Explore anything with the first
computational knowledge engine.
MathWorld »
The web's most extensive
mathematics resource.
Course Assistant Apps »
An app for every course—
right in the palm of your hand.
Wolfram Blog »
Read our views on math,
science, and technology.
Computable Document Format »
The format that makes Demonstrations
(and any information) easy to share and
interact with.
STEM Initiative »
Programs & resources for
educators, schools & students.
Computerbasedmath.org »
Join the initiative for modernizing
math education.
Step-by-Step Solutions »
Walk through homework problems one step at a time, with hints to help along the way.
Wolfram Problem Generator »
Unlimited random practice problems and answers with built-in step-by-step solutions. Practice online or make a printable study sheet.
Wolfram Language »
Knowledge-based programming for everyone.
Powered by Wolfram Mathematica © 2018 Wolfram Demonstrations Project & Contributors  |  Terms of Use  |  Privacy Policy  |  RSS Give us your feedback
Note: To run this Demonstration you need Mathematica 7+ or the free Mathematica Player 7EX
Download or upgrade to Mathematica Player 7EX
I already have Mathematica Player or Mathematica 7+