Ordinary light and monochromatic light

[gracy]

every one with its own E/B fields perpendicular to each other

And also perpendicular to the direction of motion of wave.

 

[essemcee]

You need to watch the Cosmos with Neil deGrasse Tyson and understand that these discoveries were paramount in the evolution of science. The wave theory was "seen" by Isaac Newton by splitting light with a prism, and infrared was discovery by accident by Herschel (control thermometer). The true nature of spectroscopy wasn't discovery until Fraunhofer magnified the spectrum, seeing the gaps between the spectral colors and to his amazement seeing a code in nature on an elemental level. On the other side, Faraday discovered the effect electromagnetism had on light (observed light pass through glass, a dielectric while creating a magnetic field), which was later backed mathematically by Maxwell. Later Einstein's Nobel prize work on the photoelectric effect put all of this work together and boom, solar panels 50 years later!

"Just as there's a gap between observing something and knowing how it works, there's a gap between knowing how something works and being able to do anything useful with it. "-https://[URL='http://www.theatlantic.com/technology/archive/2014/09/einstein-didnt-win-a-nobel-for-relativity-he-won-it-for-this/380451/']www.theatlantic.com/technology/archive/2014/09/einstein-didnt-win-a-nobel-for-relativity-he-won-it-for-this/380451/[/URL]

 

[DrDu]

Gracy,
maybe the analogy to sound is helpful. Sound is also propagating waves. If you press just one key on a piano, you will get approximately a "monochromatic" wave. If you play an accord, this corresponds to polychromatic light (Btw. note, that "chromatic" has a completely different meaning in music). White light is best compared to the noise coming off a radio which is not set to some radio station. So there are lots of frequencies or sound wavelength whose intensity changes quite erratically. In air, the sound waves are just compressions and expansions of the air, so sound waves have no polarisation. In solids, there can also be transversally polarised sound, i.e., the medium is shifted perpendicularly to the propagation direction, just like when you wiggle a rope. Light, at least in air or vacuum, is always perpendicularly polarised. In former times, people thought that electromagnetic waves are carried by a medium too, which they called aether, but gradually they found out, that no such medium exists and that what oscillates in light is the strenght of electric and magnetic fields.