Model of light

[QuantumJG]

Okay well I'll start from the top in that I get how light is what it is when it comes in contact with matter.

Then comes to electromagnetic wave model. From here I am completely lost.


The electromagnetic wave model of light states that, in its interactions
with matter, light acts like a three-dimensional, transverse, electro magnetic
wave. Whenever an electric fi eld waggles back and forth in one dimension,
a magnetic fi eld waggles back and forth in another dimen sion, and there is
a wave produced in the third dimension that travels at the speed of light.


I hit my head on the table after "three dimensional, transverse, electro magnetic wave" . Well not literally aha

With light you have:

- The Ray model which is great for optics as you picture light as straight lines. So you can look at say your shadow and see the shape of your hand and then if you look closely at the shadow it's kind of fuzzy around the edges from light diffracting around your hand.

- That brings us to the wave model of light which explains this diffraction.

- The photon model comes from the wave-particle duality (Unit 4 intro to quantum mechanics). I wouldn't worry about this.

An Electromagnetic wave (light) is basically a self propagating wave in which a changing electric field creates a magnetic field that changes to create an electricfield through electromagnetic induction.

Maxwell's equations show this.

- The first equation 'Gauss's's law' states that a charged particle has it's own electric field.
- The second equation 'Gauss's law for magnetism' states magnetic monopoles do NOT exist (yet to be confirmed - we were asked in a tutorial to think of how that equation would change if the did exist)
- The third equation 'Faraday's law - you'll look at this guy in Unit 4' says that a changing magnetic field creates an electric field.   
- The fourth equation 'Ampere-Maxwell law - It was Ampere's law until Maxwell saw it was incomplete' say's that a changing electric field creates a magnetic field.

Obviously you guys don't need to look at them, but they are my favourite equations and it's interesting to see that light and electromagnetism are literally the same thing.

[Studyinghard]

hm well this all makes a little more sense the more I read. Thanks all <3