Re: what is a scattered light's instensity determined by?

Denise,

You actually ask a very complicated question.  Scattered light occurs when 
light hits "something" and some of the energy from the incident wave is 
reemitted.  The intensity of the light after interacting with the 
"something" consequently depends on what that something is.  For instance, 
light scattered by objects which are small in comparison to the wavelength 
is known as Rayleigh scattering.  Lord Rayleigh discovered that when light 
was scattered by very small particles, the intensity (or more accurately, 
the scattered flux density) is proportional to the fourth power of the 
incident frequency (or f^4).  On the other hand, if the "something" is 
approximately the same size as the wavelength of the incident light, we can 
see a whole range of colors.

If you're really interested in knowing more, Gustave Mie published a 
rigorous solution of this scattering problem for particles of any size back 
in 1908.  Though I have not read this article, I did see it referred to in 
several of my favorite references.  One of these references (Hecht's 
"Optics", 1987) states, "Although complicated, [Mie's] solution has great 
practical value, particularly when applied to colloidal and metallic 
suspensions, interstellar particles, fog, clouds, and the solar corona, to 
mention only a few."  You may want to pursue this further if you're still 
curious!

Good luck,
Amber