Understanding Electromagnetic Waves

[FOIWATER]

I am having trouble understanding how a light wave travels through a medium, such as the Earth's atmosphere when emitted from a light bulb...

I have read some topics on the difference between transverse and longitudinal waves, but I am having trouble understanding how they exist.

I can imagine radiation existing as being emitted from a source, in all directions, and the intensity of the radiation over time follows a sine wave, and the period of this sine wave determines the color of the light, IE, how often the radiation peaks and crests in intensity over time. That's kind of how I imagine it, but is it correct.

 

[nsaspook]

I am having trouble understanding how a light wave travels through a medium, such as the Earth's atmosphere when emitted from a light bulb...

Can you be more specific, as our atmosphere is mostly empty space to visible light.

http://en.wikipedia.org/wiki/Speed_of_light#In_a_medium

 

[FOIWATER]

empty space, than.

 

[nsaspook]

A simple device to detect the E field of a wave.


http://www.youtube.com/watch?v=p5Mfv6shyLw&feature=related

 

[sophiecentaur]

A simple device to detect the E field of a wave.

A very good demo but marred by the emphasis on practical details and an illegible white board diagram. They must have been very chuffed when they got it working and could 'feel' the wavefronts!