# Boundary behaviour

1. Dec 4, 2011

### Misr

Hellllllllllo World
1-
[url]http://www.physicsclassroom.com/Class/refrn/u14l3a1.gif[/url]

When a light ray falls on the boundary between two media , some of the energy is reflected back to the first medium,some energy refracts and some energy is absorbed.
how is this exlplained?does it has something to do with the natural frequency of the electrons?

A light ray is a combination of different wavelengths ( different frequencies),if some frequencies were the same as the natural frequencies of the elctrons of water,they are absorbed and the other wavelengths are refracted and reflected.
Is that true?I mean does this explains the previous?Actually,I don't think so.

but this begs another question:What does the intensity of refraction and reflection depends upon?we study that it depends upon the difference between speed of light in the two median light falls from air to water ,most of the energy is reflected since the difference in speed between the two media is great.How to explain something like this?

2-I have a big misconception about diffraction:I think that in order for difrraction to occur, the wavelength must be smaller than the dimensions of the slit

if the wavelength is larger than the dimensions of the slit,diffraction cannot occur.
I got this misconception from the equation :
http://library.thinkquest.org/19537/media/equation1.gif
http://library.thinkquest.org/19537/Physics6.html
and since the value of the sine cannot be larger than one , I concluded the previous MISCONCEPTION
and also According to the equation,we can conclude that diffraction is greatest when the wavelength is equal to the dimensions of the slit
okay,
why do I call this a "misconception"?